Answer: 28.8 (choice D)
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Step-by-step explanation:
We have similar triangles, so we can use a proportion to solve for x.
25/12 = (25+35)/x
25/12 = 60/x
25x = 12*60
25x = 720
x = 720/25
x = 28.8
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Another way to set up the proportion could be:
25/(25+35) = 12/x
25/60 = 12/x
25x = 60*12
25x = 720
x = 720/25
x = 28.8