Question

FAN AND MEDAL!!!!!!

Complete the square of the function y = −5x2 + 10x + 12.

Part A: Where is the vertex located and what is the maximum or minimum value? What is the equation of the axis of symmetry?

Part B: What are the zeros of the function (as exact values expressed in radical form) and the y-intercept?

Answer 1

well for the terms in x, factor out -5

so \[y = -5(x^2 -2x) + 12\]

now you should be able to complete the square in x.

Answer 2

since you have -5x^2 the curve has a maximum at the vertex

for part B since they say leave the solution as a radical, you need to use the general quadratic formula to find the zeros

Answer 3

okay so the maximum would be 1?

Answer 4

i dont understand any of this

Answer 5

well you need to complete the square...

so you have

\[x^2 - 2x + ? \]

makes a perfect square

Answer 6

if you don't understand any of it, then it makes it difficult to explain...

here is a site that does a good job to explain completing the square

https://www.mathsisfun.com/algebra/completing-square.html

Answer 7

this site talks about completing the square to find the vertex

http://www.purplemath.com/modules/sqrvertx.htm

Answer 8

hope it helps you

Answer 9

Thank you