Question

What is the equation for the line?

Answer 1

Y=mx+b equation for line

Answer 2

I agree, you would use the formula, "y=mx+b" to solve this graph. First, you find to exact points within the graph. In this case, you have (0,0)  (-2-,16), and (2,16).

So choosing two out of these points, you will solve for "m", which is your slope. In order to find the slope, you will use the y1-y2 over x1-x2 formula.
[I chose the two points (-2, -16) and (2, 16)]:

16-(-16)      32
---------- =  ------
2-(-2)          4

Taking this fraction, you will simplify it to 8. (Since 4 can go into 32, eight times)

Now that you have your slope, substitute it into your "y=mx+b" equation where m is:
y=8x+b

Though, you don't have your b, your y-intercept, so you can either insert one of your two points you used to find slope OR you can find where the line intersects along the y-axis. 

Solving process for "b", using the point (2, 16):

y=8x+b
16=8(2)+b  --> SUBSTITUTE the points into it's perspective slots/places.  
16=16+b --> SUBTRACT, so that b is isolated.
-16  -16
-----------
0=b --> This is your y-intercept. 

So your final answer all together for the graph is: y=8x+0