Solve left(a+bright)=a+b^3-2left(a+bright)+a+b-9

$$\left( a+b \right) =a+ { b }^{ 3 } -2 \left( a+b \right) +a+b-9$$

Solve for a

$$a=b^{3}-2b-9$$

Solution Steps

Use the distributive property to multiply -2 by a+b.

$$a+b=a+b^{3}-2a-2b+a+b-9$$

Combine a and -2a to get -a.

$$a+b=-a+b^{3}-2b+a+b-9$$

Combine -a and a to get 0.

$$a+b=b^{3}-2b+b-9$$

Combine -2b and b to get -b.

$$a+b=b^{3}-b-9$$

Subtract b from both sides.

$$a=b^{3}-b-9-b$$

Combine -b and -b to get -2b.

$$a=b^{3}-2b-9$$