2015 AMC 8 Problems/Problem 8
What is the smallest whole number larger than the perimeter of any triangle with a side of length and a side of length ?
Solution
By the triangle inequality rule, the last side has to be 23. 5 + 19 + 23 = 47. Therefore D, 48 is correct.
Solution 2
By the triangle inequality rule, the last side has to be less than the sum of the other 2 sides. If we assign the value p for the final side length, then p < 5 + 19. This simplifies to p < 24. If we add 5 + 19 to both sides of the inequality, then we get p + 5 + 19 < 24 + 5 + 19. If you simplify the right side, you will get p + 5 + 19 < 48. Notice that p + 5 + 19 is the perimeter of the triangle, and the inequality shows that the perimeter is less than 48, so our answer is . Re-posted by Sagadu. Original by someone else.
See Also
2015 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 7 |
Followed by Problem 9 | |
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