Since you have the answers, I'll just show the steps on how to get there.
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Problem 19
[tex](1+4i)^2\\\\(1+4i)(1+4i)\\\\1*1 + 1*4i + 4i*1 + 4i*4i\\\\1 + 4i + 4i + 16i^2\\\\1 + 4i + 4i + 16(-1)\\\\1 + 4i + 4i-16\\\\(1-16) + (4i+4i)\\\\(1-16) + (4+4)i\\\\-15 + 8i\\\\[/tex]
Keep in mind that [tex]i = \sqrt{-1}[/tex] by definition. Squaring both sides leads to [tex]i^2 = -1[/tex]
In the second step, I used the idea that x^2 = x*x. Right after that, I used the FOIL rule to expand everything out.
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Problem 21
We could follow the same idea as problem 19, but I'll use a different approach.
[tex](A+B)^2 = A^2+2AB+B^2\\\\(3+i)^2 = 3^2 + 2*3*i + i^2\\\\(3+i)^2 = 9 + 6i - 1\\\\(3+i)^2 = 8 + 6i\\\\[/tex]
The formula on the first line is the perfect square binomial formula.
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Problem 23
The FOIL rule can be used if you want, but I'll use the difference of squares rule instead.
[tex](m+n)(m-n) = m^2 - n^2\\\\(3+5i)(3-5i) = (3)^2 - (5i)^2\\\\(3+5i)(3-5i) = 9 - 25i^2\\\\(3+5i)(3-5i) = 9 - 25(-1)\\\\(3+5i)(3-5i) = 9 + 25\\\\(3+5i)(3-5i) = 34\\\\[/tex]
It turns out that multiplying any complex number of the form a+bi with its conjugate a-bi will result in a purely real number (that has no imaginary part). More specifically: [tex](a+bi)(a-bi) = a^2+b^2[/tex]
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Problem 25
We could use the difference of squares rule again, but I'll show a different approach. This time using the distribution rule. The FOIL rule could also be used if you wanted.
[tex](6+7i)(6-7i)\\\\x(6-7i)\\\\6x-7xi\\\\6(x)-7i(x)\\\\6(6+7i)-7i(6+7i)\\\\6(6)+6(7i)-7i(6)-7i(7i)\\\\36+42i-42i-49i^2\\\\36-49(-1)\\\\36+49\\\\85\\\\[/tex]
I used x = 6+7i and the substitution property to help distribute. Lines 3 and 6 are where distribution is applied.
I need help on this ASAP… Line A passes through the points (-4,5) and (0,2). Line B…
Answer:
Parallel lines: Line B and C
Perpendicular lines: Line A and B; Line A and C
Step-by-step explanation:
To answer this question, we only need to find the slope of each equation. The formula for slope is attached in a picture.
LINE A
Substituting the first line into the formula, we will get...
(2 - 5)/(0 -(-4))
-3/4
LINE B
Substituting the second line's points into the formula we will get...
(2 - 6)/(3 - 6)
-4/-3
4/3
LINE C
Substituting the third line's points into the formula we will get...
(3 -(-1)/(0 -(-3))
4/3
So, parallel lines have the same slope, right? Since line b and line c have the same slope, they are parallel.
And, perpendicular lines have negative reciprocal slopes, right? (reciprocal means x/y -> y/x) Since -3/4 and 4/3 are negative reciprocals of each other, they are perpendicular.
Therefore...
Parallel lines: Line B and C
Perpendicular lines: Line A and B; Line A and C
THE SIDES OF A TRIANGLE ARE IN THE RATIO 4:4:3. A.WHAT KIND OF TRIANGLE IS IT? B. CALCULATE THE SMALLEST ANGLE OF THE TRIANGLE TO THE NEAREST DEGREE.
Answer:
1
Step-by-step explanation:
Violet is playing a board game with her friends. She earned 78 points during the game, and she receives a game-end bonus for achieving her secret objective. With her bonus, Violet came in second place with 91 points. Let b be the number of points Violet earned for the game-end bonus. Write and solve the equation for b.
Answer:
78 + B = 91...
91 - 78 = B
91 - 78 = 13
B = 13
Step-by-step explanation:
If x−3=5, what is the value of 2(x+4)?
Answer:
24
Step-by-step explanation:
x-3=5, solve for x so that x=5+3
now put this in place of x in the expression 2(x+4)
2[(5+3)+4]
2(8+4)
2(12)
24
plzz help asap plzzzzz
Answer:
5.45 then 6.454 then 5425 then 12825
Step-by-step explanation:
In the equation y ≈7x-9,if x≥2, then what is the value of y?
Answer:
y[tex]\geq[/tex]5
Step-by-step explanation:
7(2)-9
14-9
5
y[tex]\geq[/tex]5
In a triangle, the exterior angle is twice of each of the interior opposite angles. The exterior angle is 120°.Find the measure of each interior opposite angle of the triangle.
Pls no Spam. 35 points is the prize
Answer:
Let X be other interior opposite angle of a △XYZ.
Let Y be the third angle.
Exterior angle is equal to sum of interior opposite angles.
120
o
=30
o
+∠X
⇒∠X=90
o
Now, Sum of interior angles of a triangle is 180
o
⇒90
o
+30
o
+∠Y=180
o
⇒∠Y=180
o
−120
o
=60
o
Step-by-step explanation:
mark me as brainlist
follow me
If ΔPQR ≅ ΔTSR, what are the congruent corresponding parts?
Answer:
If ΔPQR ≅ ΔTSR
Angles:
P and T
Q and S
R and R
Lines:
PQ and TS
QR and SR
PR and TR
7.
Identify the vertex of the parabola.
A. (1, 2)
B. (−2, −1)
C. (−1, −2)
D. (−3, 2)
Answer: I can't find the answer :(
B. (−2, −1)
Step-by-step explanation: I don't know :(
From when I am looking at the graph it looks like the answer would be
P= (-2, -1)
Q= (1, -2)
Which equation is linear? y=x4 y=xy –x3 ОООС f(x) = 3х + 1 y=xУ
Answer:
f(x) = 3х + 1
Step-by-step explanation:
Suppose an annuity pays 7.0% annual interest, compounded annually. If you invest $3,000 every year for 5 years, what percentage of the balance in the account is interest earned?
Round your answer to the nearest hundredth of a percent.
Answer:
13.05%
Step-by-step explanation:
The value of an ordinary annuity earning interest compounded annually is ...
A = P((1 +r)^n -1)/r . . . . . interest rate r for n years on principal payments P
For this account, the balance after 5 years will be ...
A = 3000((1 +.07)^5 -1)/0.07 = 3000·5.750739
The sum of payments is ...
payment total = 3000·5
Then the amount of interest is ...
3000·(5.750739 -5) = 3000·0.750739
and the fraction that is of the account balance is ...
(3000·0.750739)/(3000·5.750739) × 100% ≈ 13.05%
About 13.05% of the balance is interest earned.
Please check the mcq in the following picture and thank you
Answer 2nd one
Step-by-step explanation:
Write an equation for the nth term of the arithmetic sequence –1, –3, –5, –7,
Answer:
[tex]a_n=-1+(n-1)(-2)[/tex]
Step-by-step explanation:
The arithmetic sequence formula looks like this:
[tex]a_n=a_1+(n-1)d[/tex]
where aₙ is the nth term, a₁ is the first term, n is the index, and d is the common difference.
Each consecutive term is decreased by 2 over the last, so d = 2. The first term is -1 of course, so you can write this equation:
[tex]a_n=-1+(n-1)(-2)[/tex]
Just to confirm:
[tex]a_n=-1+(n-1)(-2)\\a_3=-1+(2)(-2)\\a_3=-1-4\\a_3=-5[/tex]
And it works, -5 is the 3rd term in the sequence.
Answer:
[tex]a_{n}[/tex] = 1 - 2n
Step-by-step explanation:
The nth term of an arithmetic sequence is
[tex]a_{n}[/tex] = a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = - 1 and d = a₂ - a₁ = - 3 - (- 1) = - 3 + 1 = - 2 , then
[tex]a_{n}[/tex] = - 1 - 2(n - 1) = - 1 - 2n + 2 = - 2n + 1 = 1 - 2n
what is the area of the triangle?
Team A beat Team B by 15 points in a football game . If a total of 35 points were scored , what was the final score of the game ?
I WILL MARK YOU A BRAINLIEST
Answer:
25-10 (25 - A and 10 - B)
Step-by-step explanation:
25 - 10 equals the 15 point margin
25 plus 10 equals the 35 point score combined
Hope it helps
100 POINTS!
A local theater has a maximum capacity of 1000 people. For their latest production, adult tickets cost $25 and youth tickets cost $12.5. The theater needs to make at least 15,000 for the show to continue.
Write and graph a system of linear equations, and write two possible solutions.
Answer:
a+y≤1000 and 25a+12.50y>15000
Step-by-step explanation:
Haala buys 13 identical shirts and 22 identical ties for £363.01 the cost of the shirt is £15.35 find the cost of the tie
Using linear system of equations, the cost tie is £7.43.
Linear equations -In everyday life, we can utilize linear equations to compare prices, make predictions, create budgets, and more. When all of the variables have a highest power of one, an equation is considered to be linear. Each variable is reliant on the others. A one-degree equation is another name for this kind of equation. Continue reading to learn how to solve a linear equation in one or two variables using its standard form, formula, graph, and rules.
Given,
Haala buys 13 identical shirts and 22 identical ties for £363.01 the cost of the shirt is £15.35,
According to question,
let cost of shirt = x
cost of tie = y
Now putting it in the equation,
13x + 22y = 363.01
given x = 15.35
⇒ y = 363.01 - 13(15.35) / 22
y = 363.01 - 199.55 / 22
y = 7.43
To learn more about linear system of equations from given link
https://brainly.com/question/25858757
#SPJ1
A shirt that normally cost $30 is on sale for $21.75 what percent of the regular price is the sale price
Answer: 72.5%
Step-by-step explanation:
I used trial and error to figure this out.
I first found a quarter of 30 which is 7.5, so the percentage is near 75% since when 7.5 is times by 3 it becomes 22.5 which is close. Then I found what one is by dividing 30 by 100 and guessed the percentages getting closer to the answer basing on whether my last answer was to low or high and found 72.5% of 30 is 21.75 so the answer is 72.5%.
Simplify the expression. w+w+5w
Answer:
w+w+5w = 7w
Step-by-step explanation:
Answer:
7w
Step-by-step explanation:
Line l is a reflection in the x-axis of line k. Write an equation that represents line k.
Answer:
(-4,3)
Step-by-step explanation:
nejsjsjssjsususheheueueyeehejebebe
Answer: y = (5/3)x + -1
Step-by-step explanation:
The slope is -5/3, so since its a reflection in the x - axis, the new slope would be the opposite, 5/3. Now for the +1, you just have to find the y intercept by plotting the dots at the opposite version of the y number that is already there. For example because the point (0,1) has 1 as its y number, you make it into -1, and for example if you have the point (3,-4) since -4 is the y number you change it to 4.
Solve the triangles for X: include the steps if you can
Answer:
10) x=9
11) x=25
Step-by-step explanation:
a triangle is 180º total
10) 2x+8x+90=180
10x=90
x=9
11) 3x+1+2x+2+2x+2=180
7x+5=180
7x=175
x=25
A calculator is selling for $80 with an 8.5% tax. How much will you pay in tax for the calculator?
Answer:
$86.80
Step-by-step explanation:
Given f(x) = 2x - 5 , find the average rate of change of f(x) from x = 2 to x = 5?
[tex]slope = m = \cfrac{rise}{run} \implies \cfrac{ f(x_2) - f(x_1)}{ x_2 - x_1}\impliedby \begin{array}{llll} average~rate\\ of~change \end{array}\\\\[-0.35em] \rule{34em}{0.25pt}\\\\ f(x)=2x - 5 \quad \begin{cases} x_1=2\\ x_2=5 \end{cases}\implies \cfrac{f(5)-f(2)}{5-2}\implies \cfrac{[2(5)-5]~~ - ~~[2(2)-5]}{3} \\\\\\ \cfrac{5-(-1)}{3}\implies \cfrac{5+1}{3}\implies 2[/tex]
Original price of shorts $53.95 Discount 30% Tax 4.5?
Please help what’s the correct answer ???
Answer:
72.8325
Step-by-step explanation:
I think it is that
(1.2•10^9) divided by (3•10^5)
Answer:
4000
Step-by-step explanation: First multiply the first two equations and will give you 1200000000 divided by 300000. Now logically 12/3is 4 so u do the same in the equation and it gives you 4000. Pls give brainly if i was right
Answer:
4000Step-by-step explanation:
(1.2•10^9) divided by (3•10^5)
(1.2 * 10^9) : (3 * 10^5) =
(1.2 * 1000000000) : (3 * 100000) =
1200000000 : 300000 =
4000
Please I did help with this
Answer:
13.1
Step-by-step explanation:
Estimate the quotient for 608 divided by 23
Answer:
18
Step-by-step explanation:
Answer:
30
Step-by-step explanation:
When estimating we round to the nearest 1.s.f
Thus...
608 rounded to the nearest 1sf
= 600
and....
23 rounded to the nearest 1sf
=20
Therefore- 600÷ 20 = 30
Hope this helped you- have a good day bro cya)
.........................
Answer:
[tex]2[/tex]
Step-by-step explanation:
Let [tex][n][/tex] denote the area of some polygon [tex]n[/tex].
The sum of the area of quadrilaterals BCDE and MNDE is equal to [tex][ABC]-([MBE]+[NDC]+AMN])[/tex] (big triangle subtracting the three smaller triangles that aren't part of BCDE or MNDE).
Let the area of triangle ABC be [tex]\alpha[/tex].
Triangle AMN is similar to triangle ABC. Because their side lengths are in ratio 1:2 respectively, the ratio of the area of triangle AMN to triangle ABC is [tex]1:2^2=1:4[/tex].
Therefore, [tex]\displaystyle [AMN]=\frac{1}{4}[ABC]=\frac{1}{4}\alpha[/tex].
Now for triangle NDC, NDC is similar to triangle AMC. Since M is the midpoint of AB, AMC is half the area of ABC. The ratio of the side lengths between triangle NDC and triangle AMC is [tex]1:2[/tex] because the D is the midpoint of MC, so it follows the ratio of their areas must be [tex]1:4[/tex], respectively.
Therefore, [tex]\displaystyle[NDC]=\frac{1}{4}[AMC]=\frac{1}{8}[ABC]=\frac{1}{8}\alpha[/tex].
We can use the same concept for triangle MEB. Triangle MEB is similar to triangle ANB, and the ratio of their sides is also [tex]1:2[/tex], since E is the midpoint of BN. Their areas are in the ratio [tex]1:2^2=1:4[/tex] and we have [tex]\displaystyle [MBE]=\frac{1}{4}[ANB]=\frac{1}{8}\alpha[/tex].
Thus,
[tex]\displaystyle \frac{[ABC]}{[BCDE]+[MNDE]}=\frac{\alpha}{\alpha-\frac{1}{4}\alpha-\frac{1}{8}\alpha-\frac{1}{8}\alpha}=\frac{\alpha}{0.5\alpha}=\frac{1}{\frac{1}{2}}=\boxed{2}[/tex]
sets if 98% of households have at least one television set and 4 households are selected, find the probability that at least one household has a television set.
Using the binomial distribution, it is found that there is a 0.99999984 = 99.999984% probability that at least one household has a television set.
For each household, there are only two possible outcomes, either it has at least one television set, or it does not. The probability of a household having at least one television set is independent of any other household, which means that the binomial distribution is used to solve this question.
Binomial probability distribution
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters are:
x is the number of successes. n is the number of trials. p is the probability of a success on a single trial.In this problem:
4 households are selected, hence [tex]n = 4[/tex].98% have at least one television set, hence [tex]p = 0.98[/tex]The probability that at least one household has a television set is:
[tex]P(X \geq 1) = 1 - P(X = 0)[/tex]
In which:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{4,0}.(0.98)^{0}.(0.02)^{4} = 0.00000016[/tex]
Then:
[tex]P(X \geq 1) = 1 - P(X = 0) = 1 - 0.00000016 = 0.99999984 [/tex]
0.99999984 = 99.999984% probability that at least one household has a television set.
A similar problem is given at https://brainly.com/question/24863377
Can someone help with question #4 please
Answer:
4,0 is the right ok I am a professor