The length, width, and height of a rectangular prism can be represented by the expression (x + 3), (x + 7) and (x - 1). write an expression to represent the surface area of the prism

A=2wl+2lh+2hw

A=2(x+7)(x+3)+2(x+3)(x-1)+2(x-1)(x+7)

A=2(x^2+7x+3x+21)+2(x^2-x+3x-3)+2(x^2+7x-x-7)

A=2(x^2+10x+21)+2(x^2-2x-3)+2(x^2+6x-7)

step-by-step explanation:

always plug in x. in this case, x equals 4.

i'm going to first solve 4(2+3x)

1) 4(2+3(4)) use pemdas to solve.

i'm going to multiply whats in the parenthesis first, so 3 times 4=12.

2)4 (2+12) i'm then going to multiply 4 by both numbers in the parenthesis (because multiplying comes before adding)

4 times 2= 8.   4 times 12= 48

4) (8+48)= 56 (answer)

i'm then going to solve 8+12x and plug in 4 for x.

1) 8 +12(4)

multiplying comes before adding, so i'm gonna multiply 12 and 4.

12 times 4= 48.

2) 8+48=56

both equal the same!

lockers 1, 4, 9, 16, 25, 40, and 49 are open

i ran through it by the other answer is wrong