What is the area of the triangle enclosed by the lines y=0,x=8 and y =x?

Since we have a horizontal line, y=0 on the x-axis, a vertical line at x=8, and a 45 degree angle line from y=x.

So you essentially have a right triangle with a base that is 8 units wide, and a side that is 8 units high.

Since the area is bh/2, A=8*8/2=32u^2