Your answers will be A,B,D,
Use the distributive property.
4a - 8 = 3a + 12
Arrange the like terms.
4a - 3a = 12 + 8
a = 20
That is the answer. <span>☺️</span>✌️
The surface area in this equation is 5x4 which is 20
All the angles are different. And It's concave.
4x + 1 = x^2 + 3x - 1
4x = x^2 + 3x - 2
0 = x^2 -x - 2
0 = x^2 -x + 1 - 3
0 = (x - 1)^2 - 3
3 = (x - 1)^2
sqrt 3=(x-1) and (-(x-1))
x = 1+sqrt 3 and 1-sqrt 3
sqrt means square root