SOLUTION: okay i have one question that i'm not sure how to set up. 1. The lengths of the sides of a triangle are in the ratio 5:6:7. describe the length of the longest side if the perimet

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Question 207703: okay i have one question that i'm not sure how to set up.
1. The lengths of the sides of a triangle are in the ratio 5:6:7. describe the length of the longest side if the perimeter is less that 54 cm.
Found 2 solutions by rfer, MathTherapy:
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
5x+6x+7x=54
18x=54
x=3
5(3)+6(3)+7(3)=54

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Since the sides of the triangle are in the ratio 5:6:7, and since its perimeter is less than 54 cm, we can say that:

5x + 6x + 7x < 54

18x < 54

x < 3

Since x is less than 3, and since the longest side is 7x, we can say that:
x < 3, and therefore:

7(x) < 7(3), or 7x < 21.

This means that the longest side, 7x, is highlight_green%28_%3C21%29