3/8 (x-1) (x-9)
graph the function

  see below

Step-by-step explanation:

The factors tell you the x-intercepts are at x=1 and x=9, as these are the x-values that make the factors zero.

The y-intercept is ...

  (3/8)(0 -1)(0 -9) = 27/8 = 3 3/8

The vertex is at the point halfway between the x-intercepts, at x = (1+9)/2 = 5.

  (3/8)(5 -1)(5 -9) = 3(-16)/8 = -6

The vertex is (5, -6)

So, we have points on the curve (0, 3 3/8), (1, 0), (5, -6), (9, 0), (10, 3 3/8)*. The graph is a smooth parabolic curve through these points.

___

* (10, 3 3/8) is symmetrically located about x=5 from the y-intercept.

x = 25

Step-by-step explanation:

25 + x + 15 = 3x - 10

x + 40 = 3x - 10

-3x         -3x

-2x + 40 = -10

      -40       -40

-2x = -50

 -2      -2

x = 25