Which of these is a function? {(0, 1),(1, 2),(1, 5),(2, 9)}
{(0,4),(0,5),(0, 9),(0,23)}
{(0.4),(2, 4),(3, 7),(4.9)}
{(6.0),(6, 1),(6, 7),(6,11)}

.25

step-by-step explanation:

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

b

step-by-step explanation:

i dont know