Question

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Answer 1

invert the subtraction by adding 8 to both sides
\[19 + 8 = \frac{h}{3} -8+8\]
\[19 + 8 = \frac{h}{3} \cancel{-8} \cancel{+8}\]
to get:
\[27 = \frac{h}{3} \]
then invert the division by multiplying both sides by 3:
\[ 3*27 = 3*\frac{h}{3}\]
which is the same as:
\[3*27 = \frac{\cancel{3}h}{\cancel{3}}\]
to get:
\[81 = h \]
and you're done.