What is the equation of line in graph 4,0 0,-4

First you want to find m (which is slope). We use point slope formula to find this. Since we have two points we can do this.


0+4 = m(4-0)
Divide both sides by 4

m=1

Now we use point slope formula. We only need one point, it doesn't matter  which, so take your pick (either 4,0 or 0,-4)
y=mx+b

0=1(4)+b

Simplify and solve for b

b=-4

Now you have your slope and y-intercept. That's all you need! :)

y=x-4 if your equation of the line

A=bxh3.2x1.8=5.76 centimeters square