r(100)=-0.5(100)2+80(100)

Rewrite the function as an equation.

y=3000

The slope-intercept form is y=mx+b, where m is the slope and b is the y-intercept.

y=mx+b

Find the values of m and b using the form y=mx+b.

m=0

b=3000

The slope of the line is the value of m, and the y-intercept is the value of b.

Slope: 0

y-intercept: 3000

Slope: 0

y-intercept: 3000

Graph r(100)=-0.5(100)^2+80(100)