90=a+2(b)

Solution for 90=a+2(b) equation:

Simplifying
90 = a + 2(b)

Solving
90 = a + 2b

Solving for variable 'a'.

Move all terms containing a to the left, all other terms to the right.

Add '-1a' to each side of the equation.
90 + -1a = a + -1a + 2b

Combine like terms: a + -1a = 0
90 + -1a = 0 + 2b
90 + -1a = 2b

Add '-90' to each side of the equation.
90 + -90 + -1a = -90 + 2b

Combine like terms: 90 + -90 = 0
0 + -1a = -90 + 2b
-1a = -90 + 2b

Divide each side by '-1'.
a = 90 + -2b

Simplifying
a = 90 + -2b