What is the equation of the line that passes through the point (-4,-8) and has a slope of 4

Answer 1

The two things you need to find to form this equation are the slope (what is it moving) and its Y intercept (when it cross the Y-axis, this happens when the point x equals 0)

Slope Intercept Formula:

y=mx+b

m = slope. slope= rise/run

b= y intercept.

The problem says the slope is 4, meaning the line goes up 4 and over 1.

So starting at (-4,8) the next point of the line would be (-3,-4), then (-2,0) , (-1,4), and (0,8)

so b = 8

Plug it in we get

y= 4x+ 8

Answer 2

Hi Layla M.,

You should do just what you do for any word problem, transform it into a math equation and solve that!

Your only choice is, how to express the equation for a line. Here, standard (slope + intercept) form works OK:

y = mx + b

then put in your known values for the given point, and for slope (m):

-8 = 4*(-4) + b

b = 16 - 8 = 8

So y = 4x + 8 is your final format for an answer.