For #6:
I believe the answer is 1) −15x^3y^3−3x^3y^2
For # 7:
I got 3) 3
First, in order to isolate the variable "x" you need to distribute:
13x - 2(x + 4) = 8x + 1
13x -2x - 8 = 8x + 1
Then you need to combine like terms
13x - 2x - 8 = 8x + 1
11x - 8 = 8x + 1
Add 8 to both sides
11x = 8x + 9
Subtract 8x on both sides
3x = 9
Now you can divide both sides by 3...
Thus x = 3
I'm actually taking algebra right now and I gotta admit algebra is tricky for sure. However, I think it'll get easier with practice :D
