Cole rewrote a quadratic function in vertex form.

h(x) = x²-6x+7

Step 1: h (x) = (x²-6x+)+7

Step 2: h (x) = (x²-6x+9)+7-9

Step 3: h (x) = (x-3)²+2

Cole said that the vertex is (3, 2). Is Cole correct? If not, identify the step in which Cole made the mistake and correct his work.

1 answer

Cole is incorrect. The mistake is in step 2 where Cole subtracted 9 from 7 instead of adding 9 to complete the square.

The corrected version should be:

Step 1: h(x) = (x² - 6x) + 7
Step 2: h(x) = (x² - 6x + 9) + 7 - 9
Step 3: h(x) = (x - 3)² - 2

Therefore, the correct vertex of the quadratic function h(x) = x² - 6x + 7 is (3, -2), not (3, 2) as Cole stated.