A= 1/2bh
fill in formula with known numbers
42= 1/2(7)h
multiply numerators on right side
42= (1*7)/2h
42= 7/2h
divide both sides by 7/2
42 ÷ 7/2= h
to divide fractions, multiply by reciprocal/inverse of 7/2
42 * 2/7= h
multiply numerators
(42 * 2)/7= h
84/7= h
12 inches= h
ANSWER: The height is 12 inches.
Hope this helps! :)
