How would I simplify these expressions? (Pre-Calculus) I know that you are supposed to multiply all of these to do so, but every time I do that, I still get the wrong answer. My textbook says that these are the answers:
19: -15 + 8i
21: 8 + 6i
23: 34
25: 85
Could anyone explain how they got these answers? Mine are way off. Is the book just wrong? In #21, how would 3 times 3 equal 8 in the answer? Am I missing something?

Since you have the answers, I'll just show the steps on how to get there.

============================================================

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.

============================================================

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.

============================================================

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]

============================================================

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.

4) 4+ 1 =
a) 5
b) 572
12
c) 51
d) 572
6
12

In 2021, Miranda records net earnings from self-employment of $158,500. She has no other gross income. Determine the amount of Miranda's self-employment tax and her for AGI income tax deduction.
In your computations round all amounts to two decimal places. Round your final answer to whole number

Cassidy places 40 stamps on each of 8 albums pages how many stamps dose she place

Show all your working.
2
3
Income tax
Everyone can earn a certain amount of money without paying tax. This
is called a Personal Allowance. They must pay tax on any earnings
over this allowance.
4
5
6
£11 850
Income tax Personal Allowance, 2018/2019
7
8
This formula gives the amount of Income tax a person pays in a year
T = 0.2 (y-p)
9
10
where T = income tax for the year
y = money earned per year
p = Personal Allowance
11
12
13
14
15
A caterer earns £1375 per month.

Point-Slope Form of a Line

Which graph represents the solutions to x > ?

Multiply.

(−3 6/7)⋅(−3 1/3)

What is the product?

Enter your answer as a simplified mixed number in the box.

write an equation to represent CJ’s total pay

I need the solution urgently plz help me with the question I will mark you brainleist​

A 95% confidence interval for the true proportion of teenagers who have been to a professional sporting event is
(0.289, 0.416). Is it reasonable to believe that more than 25% of teenagers have been to a professional sporting
event?
O Yes, because 0.3525 is in the interval.
O Yes, because the entire interval is greater than 0.25.
O No, because there are values in the interval greater than 0.3525.
O No, because the center of the interval is 0.3525, which is not statistically greater than 0.25.

30x^8-4x^7+6x^4/-6x^3 perform division

Solve for g.
16g–11g+g=6
g=

A tortoise is walking in the desert. It walks 5.12 meters in 2 minutes. What is its speed?

Richard purchases a box of 12 cookies and Meghan purchases a bag of 10 cookies. Richard ate x amount of cookies from his box while Meagan ate half the number of cookies Richard ate. How many cookies did Richard eat if they had the same number of cookies left

If cos θ = sin 2 θ, then the value of θ is = ___?​

Series
What number should replace
the question mark? (2,3)(3,22)(4,59)(5,?)

I need help solve the equation

what is 2.4g-2.4g-9.8g

Which shows the expanded form of the number 54.98?
O a. 5x10+4x1+9x1+8 x 10
B. 5 x 10+ 4x1 +9 x 10+ 8 x 100
C 5x 10+4x1+9x to +8 100
10
D. 5 x 1000 + 4 x 100 + 9 x 10 + 8

In type 1 diabetes, the immune system attacks certain cells in the pancreas.

Question 2 options:
True
False

At a concert the ratio of adults to children is 4:5. There are 720 children in a concert how many adults are there?

BRAINLIEST QUEATION !!

SOLVE PLZ I give brainlest
17+ -9

A. 26

B. 8

C. -8

D.-26

PLEASE HELP I HAVE 3 MINUTES LEFT TO DO THIS TY
Which expression is equivalent to 5(8 + 9)?
O 40 + 45
O 13 + 9
O 13 + 14
O 40 + 9

he population of a particular town is given by the function P(t) = 1,200(1.05)2t, where t is the time in years and P(t) is the population after t years. What is the current population, the percentage growth rate, and the population size (rounded to the nearest whole person) in 7 years?

Hint: Percentage Growth Rate = r ⋅ 100 in A = A0(1 + r)t (4 points)

1,200, 5% annually, and 1,689
1,200, 50% semiannually, and 20,503
1,200, 10.5% per year, and 2,414
1,200, 5% semiannually, and 2,376

A. What does each of these points represent in the is situation: (0, 0), (1, 55), and (5, 275)?

What does each of these points represent in this situation (0, 0), (1, 55) and (5, 275)? Graph shows Mr. Brown’s road trip, with time (h) on the x-axis and distance (mi) on the y-axis. Points marked on the line graph are at (0, 0), (1, 55) and (5, 275).

Solve for u.
–
7u–u+2u+11u=10
u=

(2³ x 2⁵) ÷ 2⁸
Solution​

Next, Kevin makes a cylinder-shaped candle. He uses a metal can as a mold. The can has a radius of 6 centimeters and a height of 18 centimeters. How much wax is needed to fill the metal can?

an investment had return of 13% if inflation was 4.1% what was your real return ?

Order of operations and cross
reduce:
I got 20/3 but I think I’m wrong