No, they are not equivalent because if you distribute the -0.5 in the expression -0.5(3x+5) you will get -1.5x-2.5 which is not the same as -1.5+2.5
$2.99 + 7% of $2.99 =
= $2.99 + 7% * $2.99
= $2.99 + 0.07 * $2.99
= $2.99 + $0.21
= $3.20
1st piece = x
2nd piece = x+2
3rd piece = x+2+3 = x+5
37 = x +x+2 + x+5 =
37 = 3x+7
30=3x
x = 30/3 = 10
1st piece = 10 inches
2nd piece = 10+2 = 12 inches
3rd piece = 10+5 = 15 inches
