True: A face of a polyhedron is simply a flat boundary that helps forms the 3D solid.
Answer:
(n + 4) *2 = 11 * 2
Step-by-step explanation:
(n + 4) *2 = 11 * 2
Divide both sides by 2

n + 4 = 11
Answer:
b = 10
Step-by-step explanation:
The area (A) of a triangle is calculated as
A =
bh ( b is the base and h the height )
Here h = 3x + 15 and A = 15x + 75, thus
× b × (3x + 15) = 15x + 75
Multiply both sides by 2 to clear the fraction
b(3x + 15) = 30x + 150
Divide both sides by (3x + 15)
b =
← factor numerator and denominator
=
← cancel the factor (x + 5) on numerator/denominator
= 
= 10
To generate the equation we set up the factors
(x+3) * (x-1) * (x-2) which equals
x^2 + 2x -3 * (x-2)
x^3 +2x^2 -3x -2x^2 -4x +6 equals
x^3 -3x -4x +6 which equals
x^3 -7x +6