Answer:
B
Step-by-step explanation:
given
A = [tex]\frac{1}{2}[/tex]([tex]b_{1}[/tex] + [tex]b_{2}[/tex])h
multiply both sides by 2 to eliminate the fraction
2A = ([tex]b_{1}[/tex] + [tex]b_{2}[/tex])h
divide both sides by the multiplier h
[tex]\frac{2A}{h}[/tex] = [tex]b_{1}[/tex] + [tex]b_{2}[/tex]
Subtract [tex]b_{2}[/tex] from both sides
[tex]\frac{2A}{h}[/tex] - [tex]b_{2}[/tex] = [tex]b_{1}[/tex], that is
[tex]b_{1}[/tex] = [tex]\frac{2A}{h}[/tex] - [tex]b_{2}[/tex]
