It depends on what it is meant to be equivalent to!
4x
12
It is equivalent to: 6x^2 -8x -8
x^2 +8x -9 is equivalent to (x+9)(x-1) when factored
5
Well, darling, you've got yourself a simple algebraic equation. Five expressions equivalent to 8x + 16 could be 2(4x + 8), 4(2x + 4), 8(x + 2), 16(x/2 + 1), and even 8x + 8 + 8. Math can be a real hoot when you know your way around it!
80*8.8 800*0.88 8000*0.088
8(x+5) is equivalent to 8x+40
It is equivalent to: 32x^2 +88x +21
16
It is equivalent to: 3x+6+5 = 3x+11