Answer :
I gotchu :)
1) 6r + 7 = 13 + 7r - Subtract 6r from both sides...
7 = 13 + r - Subtract 13 from both sides....
r = -6 Check answer (don't need this part)
6(-6) + 7 = 13 + 7(-6)
-36 + 7 = 13 -42
-29 = -29 ( It works )
2) -14 + 6b + 7 - 2b = 1 + 5b - Combine like terms...
-7 + 4b = 1 + 5b - Add 7 to both sides....
4b = 8 + 5b - Subtract 5b from both sides....
-b = 8 - Divide both sides by -1
b = -8
3) 8x + 4(4x+3) = 4(6x + 4) - 4 - Distributive property
8x + 16x + 12 = 24x + 16 - 4 Combine like terms
24x + 12 = 24x + 12 - Both terms equal each other
0 = 0
Since both terms equal each other, all numbres fit.