using the similar triangles below, solve for x !
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Answer:
Step-by-step explanation:
Remarks.
This can be solved as a proportion. A proportion is 2 ratios making a total of 4 parts. If we know 3 of the parts, we can solve for the 4th.
63/(8x - 2) = 49 /42
Notice that the given parts of the top triangle are the numerators of the ratios. The 2 parts of the bottom triangle are the denominators of the proportions
Proportion
63/(8x - 2) = 49 /42
Solution
63/(8x - 2) = 49 /42 Cross Multiply
(8x - 2)*49 = 63 * 42 Combine the right.
(8x - 2)*49 = 2646 Divide by 49
8x - 2 = 54 Add 2 to both sides
8x -2+2=54+2 Combine
8x = 56 Divide by 8
8x/8 = 56/8
Answer: x = 7