Answer:
13. 108 inches
14. not similar (sides have different ratios)
15. 68
Explanation:
13. You have two relationships between length and width:
2L + 2W = 336 . . . . . the perimeter is 336 inches
L/W = 9/5 . . . . . . . . . .the ratio of length to width is 9/5
Multiplying the second equation by 5/9W, we get
5/9L = W
Now we can substitute that into the first equation to get ...
2L +2(5/9L) = 336
Multiplying by 9 gives us ...
18L +10L = 3024
And dividing by 28 gives ...
3024/28 = L = 108 . . . . inches
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14. Shortest to longest, the ratios of sides are 6 : 8 : 9 and 2 : 4 : 5. There is no value that will multiply the first ratio to give the second ratio. For example, multiplying by 1/3 gives ...
2 : 2 2/3 : 3 . . . . not 2 : 4 : 5
Similar triangles have the same side ratios. These do not, so they are not similar triangles.
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15. MP is a midsegment of triangle JKL and parallel to base JL. A midsegment is half the length of the parallel base. Then JL is twice as long as MP. JL is 68 units long.