Question 1166464
solve the equation for h 

A= 1/2 bh 
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If it's A = (1/2)bh:
Multiply by 2
Divide by b
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If it's A = 1/(2bh):
Invert
1/A = 2bh
Divide by 2b
1/(2Ab) = h
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Parentheses are free.  Use some.
Or A= 1/2 bh ----> A = bh/2