Please help i'm taking a test, and when you get the answer please explain how you got it!!

y = 122.57

Explanation:

y = 143 when x = 49

Y varies directly with x, so the equation is --> y = kx (k would be the constant of variation).

k = y/x = 143/49

y = (143/49) x

When x = 42 --> y = (143/49) · 42 --> y = 2.92 · 42 --> y = 122.57

y = 3x+4

step-by-step explanation:

to find the slope

slope = (y2-y1)/ (x2-x1)

    = (-8-4)/ (-4-0)

    = -12/-4

  = 3

using the slope intercept form of a line

y= mx+b

we know the slope is 3

we know the y intercept is 4 ( the point where it crosses the y axis or x=0)

y = 3x+4