<h3>Answer: 60</h3>
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How to get this answer:
The triangles are similar so the horizontal sides divide to get some ratio R
R = (long horizontal)/(short horizontal)
R = h/45
At the same time, the slanted sides divide in a similar fashion to get the same ratio R
R = (long slanted)/(short slanted)
R = (17+51)/(51)
R = 68/51
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Because we have the same R value, we can set the fractions equal to one another. Then we can isolate h
h/45 = 68/51
51*h = 45*68 ... cross multiply
51*h = 3060
51h/51 = 3060/51 ... divide both sides by 51
h = 60
