Enter an expression in the box to write a quadratic function given the vertex (7,-4) and the point (5, 8).

Step-by-step explanation:

The vertex form of an equation of the parabola:  

                                                       f(x) = a(x - h)² + k

the vertex is (7, -4)  ⇒   h = 7,  k = -4

so:

     f(x) = a(x - 7)² + (-4)

    f(x) = a(x - 7)² - 4

The parabola goes through the point (5, 8) ⇒   x=5,  f(x)=8

8 = a(5 - 7)²  - 4

8 = a(-2)²  - 4

+4           +4

12  = 4a

÷4       ÷4

a = 3

It means the equation of the parabola in vertex form:

                               f(x) = 3(x - 7)² - 4

sas (side angle side)

aa (angle angle)

sss(side side side)

sas find two sides with an angle in between

aa is finding two angles and the third will add up to 180

sss find all sides

step-by-step explanation: