+118651 ok So you want to make b the subject of the equation :))
\(A=\frac{1}{2}bh\\ \)
To get b on its own you have to get rid of the 1/2 and the h on the right hand side.
To do you do that??
Well if you multiply the right by 2 you will get rif of the 1/2 BUT if you do it to the right you must do it to the left side as well.
\(A=\frac{1}{2}bh\\ A*2=\frac{1}{\not{2}}bh*\not{2}\\ 2A=bh\\ \)
Good - Now you want to get rid of the h on the right if you divide by h that will work but divide the other side by h as well!
Also the fraction line IS a divide sign :))
\(2A=bh\\ \frac{2A}{h}=\frac{b\not{h}}{\not{h}}\\ \frac{2A}{h}=b\\ \mbox{Now swap sides}\\ b=\frac{2A}{h}\)
