Question

How do you solve for `B` in `A= \frac { 1} { 2} h ( b + B)`?

Answer 1

`(2A)/h-b=B`

Explanation:

`A=1/2h(b+B)`

Multiplying `color(red)2" & "color(red)(1/h` from both sides to isolate `(b+B)` on `RHS`:-

`color(red)(2times 1/h)timesA=1/cancel2cancelh(b+B)timescolor(red)(cancel2times 1/cancelh`

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

Subtracting `color(blue)b` from both sides:-

`=(2A)/hcolor(blue)(-b)=cancelb+Bcolor(blue)(cancel(-b`

`=>(2A)/h-b=B`