Becky needs the regular shade of purple for her artwork. which ratio of red paint to blue paint will she use? how many ounces of blue paint will becky mix with 4 ounces of red paint? a) 1: 1; 4 ounces b) 1: 2; 4 ounces c) 1: 3; 1 ounce d) 2: 1; 2 ounces

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15