Question

y=12 when x=4
a.

y = 3x
b.

y =1/3x
c.

y = 4x


d.

y = − 3x

Answer 1

try the numberse in each and check if the answer is right

Answer 2

y = k x is the formula for variation

plug in numbers

\(\color{blue}{ 12 = 4 \times k }\) or \(\color{blue}{ 12 = 4k }\)
k=3


knowing that k=3, plug in 3 for k, into the y=kx.

What do you get?