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Write an equation given the he vertex form and a point. vertex(3,2)and pass through the point(-1 -2)

1 Answer

2 votes

Answer:
\bold{y=-(1)/(4)(x-3)^2+2}

Explanation:

The vertex form of a quadratic equation is: y = a(x - h)² + k, where

  • (h, k) is the vertex
  • "a" is the vertical stretch

Input the vertex (3, 2) and the point (-1, -2) into the equation to solve for "a":


-2 = a(-1-3)^2+2\\\\-2=a(-4)^2+2\\\\-2=16a+2\\\\-4=16a\\\\(-4)/(16)=(16)/(16)a\\\\-(1)/(4)=a

Now, input the vertex and the a-value into the equation:


y=-(1)/(4)(x-3)^2+2

User Alexandre Ardhuin
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