Answer:
y = - (x - 2)² + 10
Step-by-step explanation:
the equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k ) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square
y = - x² + 4x + 6 ( factor out - 1 from the first 2 terms )
y = - (x² - 4x) + 6
To complete the square
add/subtract ( half the coefficient of the x- term )² to x² - 4x
y = - (x² + 2(- 2) + 4 - 4) + 6
y = - (x - 2)² + 4 + 6
y = - (x - 2)² + 10 ← in vertex form