1) 8(3a+6) = 9(2a-4)
First, we use distributive property on both sides.
Once we do this, we get:
24a + 48 = 18a - 36
Add 36 to each side.
24a + 84 = 18a
Subtract 24a from each side.
84 = -6a
Divide each side by -6
-14 = a
2) 6(2x-8)+3 = 15
Again, we use distributive property:
12x-48+3 = 15
Subtract 3 from each side
12x - 48 = 12
Add 48 to each side
12x = 60
Divide each side by 12
x = 5
3) -5(3x+6) = -3(4m-2)
Distributive property:
-15m - 30 = -12m + 6
Add 30 to each side
-15m = -12m + 36
Add 12m from each side
-3m = 36
Divide each side by -3
m = -12