SOLUTION: Find the coefficient a,b, & c for quadratic equation y=ax^2+bx+c if graph has a max at (1,8) and passes through (3,0). Is 1,8 my vertex? is c 1/2?

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Find the coefficient a,b, & c for quadratic equation y=ax^2+bx+c if graph has a max at (1,8) and passes through (3,0). Is 1,8 my vertex? is c 1/2?      Log On


   

Question 961632: Find the coefficient a,b, & c for quadratic equation y=ax^2+bx+c if graph has a max at (1,8) and passes through (3,0). Is 1,8 my vertex? is c 1/2?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
ax%5E2%2Bbx%2Bc=y

system%28a%2A1%5E2%2Bb%2A1%2Bc=8%2Ca%2A9%2Bb%2A3%2Bc=0%29

system%28a%2Bb%2Bc=8%2C9a%2B3b%2Bc=0%29

Not useful.

USE STANDARD FORM!
y=a%28x-h%29%5E2%2Bk, the vertex being (h,k).
system%28y=a%28x-1%29%5E2%2B8%2C0=a%283-1%29%5E2%2B0%29
Important is to know how these two specific equations are found; and then you can continue solving for a, and you can finish the quadratic equation.


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YES, the given maximum, (1,8), IS THE VERTEX.
The question or instruction was to find coefficients a, b, and c. You can simply take your standard form finished equation, and perform the operations to simplify into general form.