Answer: B) 4 & 1/6
Nice work on getting the correct answer.
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Step-by-step explanation:
x is opposite the marked acute angle
5 is opposite the corresponding acute angle
So x and 5 are proportional to each other. We can form the ratio x/5
Similarly, 10 and 12 are proportional to one another. We can form the ratio 10/12.
Set those ratios equal to each other and solve for x
x/5 = 10/12
12x = 5*10 ... cross multiply
12x = 50
x = 50/12 ...... divide both sides by 12
x = (25*2)/(6*2)
x = 25/6
x = (24+1)/6
x = 24/6 + 1/6
x = 4 + 1/6
x = 4 & 1/6 which shows why choice B is the answer.
Side note: 25/6 = 4.167 approximately