8x+4y=-20 and -4x-8y=-20 solve each system by substitution

Answers

Answer 1

Answer: 8x + 4y = -20
4y = -20 - 8x
y = -5 -2x

-4x - 8y = -20
-4x - 8(-5-2x) = -20
-4x + 40 + 16x = -20
12x = -60
x = -5

8(-5) + 4y = -20
-40 + 4y = -20
4y = 20
y = 5

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What is 150/100 as a decimal and percent please make sure you know. Im doing homework.

Answers

Lets first convert it to a decimal by dividing the numerator by the denominator;
150 ÷ 100 = 1.5
Now we could convert the decimal to a percent by moving the decimal point two times to the right and add the percent sign;
1.5 = 150%
so 150/100 in decimal form and percent form is; 1.5 & 150%

It would be 1.5

Think as 100 as a whole number or 1

I have 3 questions needed! Help please! You can get 25 points! Please please please help me! Thanks!1) Chole spent 15% of her allowance this month on bread. If she spent $45 on the bread, what was the total allowance?

2) A table cost $350. There is also a sales tax of 7%. How much does the table costs including the sales tax?

3) Joey bought a vintage t-shirt for $20. Then she turned around and sold it on eBay for $26. What was the percent increase in the price of the shirt?

Answers

1. so we are looking for how much her allowance is. Well we know that to get a percentage we just have to do the part over the whole and multiply by 100

so our equation looks like this
(45/x) *100 = 15%

we can change it to
45/x = .15
we need to solve for x. so let get
45 = .15x
45/.15 = x

x = 300

2. You do this by first finding out how much tax there is so
350 * .07 = 24.5
now add that to 35
350 + 24.5 = 374.5

3. So we got figure out how much she marked it up it just like the tax problem but in reverse
26 - 20 = 6
20 * x = 6
where x is the percent we are looking for

x = 6/20
x = .3
so she marked up 30%

Ms.stoner purchased a new computer for $1,150 at the apple store. If sales tax is 7.5% what was the total of her purchase

Answers

First convert 7.5% into a decimal (.075)
1,150 * .075 = 86.25
1,150 + 86.25 = 1,236.25

Answer:

1,236.25

Step-by-step explanation:

What is 0.04 times 7.6? Using ur work

Answers

Well, you'll multiply regularly, then move da decimals to the left 3 times, because if you add the amount of decimal places in 0.04 and 7.6, (2 + 1), it equals 2, but so 0.04 times 7.6 = 0.304
I hope I helped! =D

Amanda is finding 11.2 divided by 14. This is what she got, 14 divided by 11.2 equals 8.0 What is her mistake and fix it. Whats her mistake?