what is the value of x in the diagram below ?
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Answer:
x = 9
Step-by-step explanation:
12^2 + a^2 = 54^2
a^2 = 54^2 - 12^2
a = sqrt (54^2 - 12^2) = 6 * sqrt(77)
Then calculate it for another triangle, where each side is 6 times shorter (as 12/2 = 6):
2^2 + (sqrt(77))^2 = x^2
x^2 = 81
x = 9