Solve a+b+c=3b

$$a + b + c = 3 b$$

Solve for a

$$a=2b-c$$

Solution Steps

Subtract b from both sides.

$$a+c=3b-b$$

Combine 3b and -b to get 2b.

$$a+c=2b$$

Subtract c from both sides.

$$a=2b-c$$

Solve for b

$$b=\frac{a+c}{2}$$

Steps for Solving Linear Equation

Subtract 3b from both sides.

$$a+b+c-3b=0$$

Combine b and -3b to get -2b.

$$a-2b+c=0$$

Subtract a from both sides. Anything subtracted from zero gives its negation.

$$-2b+c=-a$$

Subtract c from both sides.

$$-2b=-a-c$$

Divide both sides by -2.

$$\frac{-2b}{-2}=\frac{-a-c}{-2}$$

Dividing by -2 undoes the multiplication by -2.

$$b=\frac{-a-c}{-2}$$

Divide -a-c by -2.

$$b=\frac{a+c}{2}$$