Answer:
vertex = (- 10, - 10 )
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
To obtain this form use the method of completing the square.
Given
h(x) = x² + 20x + 90
add/subtract ( half the coefficient of the x- term )²
h(x) = x² + 2(10)x + 100 - 100 + 90
= (x + 10)² - 10 ← in vertex form
with (h, k ) = (- 10, - 10 )
Start with the parentheses first
4.6 -4.4+7.8 then calculate from left to right
= 0.2+7.8 = 8
3x+7=3x+2 (cancel equal terms)
7=2 ( the statement is false)
Check the picture below.
the lateral area, namely the area of the sides, as you see in the picture, is really just the area of 6 rectangles.
front and back, two rectangles of 5x25,
left and right, two rectangles of 2x25.
simply get the area of each and sum them up, that's the lateral area of the prism.