Write an equation of a parabola with x intercept at (1/4,0) and (-7,0) which passes through the point (0,7)

Answer 1

Ax^2 + Bx + C = y

(0,7) ---> C = 7 so y = Ax^2 + Bx + 7

(1/4, 0) and (-7,0) are solutions

(1/16)A + (1/4)B + 7 = 0

A + 4B + 112 = 0

A + 4B = -112

49A - 7B + 7 = 0

7A - B + 1 = 0

7A +1 = B

A + 4(7A+1) = -112

29A + 4 = -112

29A = -116

A= -4

B = -27

-4x^2-27x + 7 = y

Answer 2

Th equation is A(x-.25)(x+7) since 1/4 and -7 are the roots.

Since the product of the roots is -7/4 and the equation passes through (0,7), a ust be -4.

A graph confirms this result.