a=3b+4c

Rewrite the equation as 3b+4c=a.

3b+4c=a

Subtract 4c from both sides of the equation.

3b=a-4c

Divide each term in 3b=a-4c by 3.

3b3=a3+-4c3

Cancel the common factor of 3.

Cancel the common factor.

3b3=a3+-4c3

Divide b by 1.

b=a3+-4c3

b=a3+-4c3

Move the negative in front of the fraction.

b=a3-4c3

b=a3-4c3

Solve for b a=3b+4c