Answer:
Step-by-step explanation:
3x^2 + 24x + 48 + 43 - 48
3(x^2 + 8x + 16) - 5
3(x + 4)^2 - 5
vertex at (-4,-5)
Answer:
vertex = (- 4, - 5 )
Step-by-step explanation:
The equation of a quadratic in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Given
y = 3x² + 24x + 43 ← factor out 3 from the first 2 terms
= 3(x² + 8x) + 43
To complete the square
add/subtract ( half the coefficient of the x- term)² to x² + 8x
y = 3(x² + 2(4)x + 16 - 16) + 43
y = 3(x + 4)² - 48 + 43
y = 3(x + 4)² - 5 ← in vertex form
with vertex = (- 4, - 5 )
