pls help and show work pls

Answer:
a) x-intercepts are (0,0) and (5,0)
b) 6.25 yards
Step-by-step explanation:
a) x intercepts are:
-x² + 5x = 0
-x(x - 5) = 0
x = 0, 5
b) -x² + 5x
-(x² - 5x)
-[x² - 2(x)(5/2) + (5/2)² - (5/2)²]
-(x - 5/2)² + 25/4
Max height is:
25/4 yards or 6.25 yards