Ava is buying paint from Amazon. Ava needs 3⁄4 cup of blue paint for every 1 cup of white paint. Ava has 28 ounces of white paint. How many cups of blue paint does he need?

21

Step-by-step explanation:

So we know the ratio is 3/4:1

So if she has 28 ounces of white pain, we can do 28*3/4=21. You could also do 28/4 (find out how much 1/4 of the value is) which is 7 and then multiply that by 3. What your basically doing is your putting it into 4 equal parts and then just multiplying by 3 since that's the amount of parts you need/have.

180

step-by-step explanation:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18