Question

Given that y = 6 + 4x-x^2express y in the form a.-(x + b)^2, where a and b are

integers. Hence or otherwise , write the coordinates of the turning point of y

Answer 1

6 + 4x − x² = 10 − (x − 2)²

the turning point : (2 , 10)

Explanation:

6 + 4x − x² = − x² + 4x + 6

= − (x² − 4x) + 6

= − (x² − 4x + 4 − 4) + 6

= − [(x − 2)² − 4] + 6

= − (x − 2)² + 4 + 6

= − (x − 2)² + 10

= 10 − (x − 2)²

Then the turning point of y is (2 , 10)