Respuesta :

Answer:

see explanation

Step-by-step explanation:

The equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k) are the coordinates of the vertex and a is a multiplier

Here (h, k) = (9, 7), thus

y = a(x - 9)² + 7

To find a substitute (3, 8) into the equation

8 = a(3 - 9)² + 7

8 = 36a + 7 ( subtract 7 from both sides )

36a = 1 ( divide both sides by 36 )

a = [tex]\frac{1}{36}[/tex]

y = [tex]\frac{1}{36}[/tex](x - 9)² + 7 ← in vertex form

Expanding the factor and simplifying

y = [tex]\frac{1}{36}[/tex](x² - 18x + 81) + 7

   = [tex]\frac{1}{36}[/tex] x² - [tex]\frac{1}{2}[/tex] x + [tex]\frac{9}{4}[/tex] + 7

   = [tex]\frac{1}{36}[/tex] x² - [tex]\frac{1}{2}[/tex] x + [tex]\frac{37}{4}[/tex] ← in standard form