ok I will help u tomorrow I am busy today
9 inches
12+12+9+9+8+8+8+8=74
12+12=24
9+9=18
8+8+8+8=32
24+18+32=74
a = 2x - 18
remove the parenthesis and simplify
x - 3 + x - a = 15
2x - 3 - a = 18 ( add 3 to both sides
2x - a = 18 ( subtract 2x from both sides )
- a = 18 - 2x ( multiply through by - 1 )
a = - 18 + 2x
a = 2x - 18