Solve for b in the formula A=1/2h (B+b)

Solution

Switch sides so that the right side is the left side

1/2h (B + b) = A

Now multiply both sides by 2

2 • 1/2h (B + b) = A • 2

Simplify the equation

h (B + b) = 2A

Now divide both sides by h

(h (B + b))/h = 2A/h

Simplify the equation

B + b = 2A/h

Subtract B from both sides

B + b - B = 2A/h - B

Simplify the equation

b = 2A/h - B

Therefore b = 2A/h - B