A triangle has an area of 9^2-9-10. The base of the triangle is 3-5. What is the height of the triangle?

(a) What is the area of the triangle determined by the lines

y = - 1/2x + 9, y = 10x, and the y-axis?

Thus we already know that

Area of triangle = 1/2*b*h

Base=9

Now to find the height, we need the coordinates of the intersection so:

-1/2x+9=10x

x=6/7 <=height

y=60/7

So using the formula

Area=1/2*b*h = 1/2*9*6/7

=3.8571428