Difference between revisions of "2008 iTest Problems/Problem 6"

m (Created page with "==Problem== Let <math>L</math> be the length of the altitude to the hypotenuse of a right triangle with legs 5 and 12. Find the least integer greater than <math>L</math>. ==Solu...")
 
m (Solution)
 
Line 3: Line 3:
  
 
==Solution==
 
==Solution==
By the Pythagorean Theorem, the hypotenuse will be <math>\sqrt{5^2 + 12^2} = \sqrt{25+144} = \sqrt{169} = 13</math>. The area of this triangle can be expressed in 2 ways: half the product of the legs, and half the product of the hypotenuse and its altitude. We can easily find the area using the first method: <math>\frac{1}{2}\cdot 5 \cdot 12 = 5\cdot 6 = 30</math>. Therefore, we have <math>\frac{1}{2}L \cdot 13 = 30</math>. Multiplying both sides by <math>2</math> and dividing both sides by <math>13</math>, we get <math>L = \frac{60}{13}</math>. The least integer greater than <math>\frac{60}{13}</math> is <math>\boxed{5}</math>
+
By the Pythagorean Theorem, the hypotenuse will be <math>\sqrt{5^2 + 12^2} = \sqrt{25+144} = \sqrt{169} = 13</math>. The area of this triangle can be expressed in 2 ways: half the product of the legs, and half the product of the hypotenuse and its altitude. We can easily find the area using the first method: <math>\frac{1}{2}\cdot 5 \cdot 12 = 5\cdot 6 = 30</math>. Therefore, we have <math>\frac{1}{2}L \cdot 13 = 30</math>. Multiplying both sides by <math>2</math> and dividing both sides by <math>13</math>, we get <math>L = \frac{60}{13}</math>. The least integer greater than <math>\frac{60}{13}</math> is <math>\boxed{5}</math>.
 +
 
 +
==See Also==
 +
{{2008 iTest box|num-b=5|num-a=7}}
 +
 
 +
[[Category:Introductory Geometry Problems]]

Latest revision as of 00:52, 22 June 2018

Problem

Let $L$ be the length of the altitude to the hypotenuse of a right triangle with legs 5 and 12. Find the least integer greater than $L$.

Solution

By the Pythagorean Theorem, the hypotenuse will be $\sqrt{5^2 + 12^2} = \sqrt{25+144} = \sqrt{169} = 13$. The area of this triangle can be expressed in 2 ways: half the product of the legs, and half the product of the hypotenuse and its altitude. We can easily find the area using the first method: $\frac{1}{2}\cdot 5 \cdot 12 = 5\cdot 6 = 30$. Therefore, we have $\frac{1}{2}L \cdot 13 = 30$. Multiplying both sides by $2$ and dividing both sides by $13$, we get $L = \frac{60}{13}$. The least integer greater than $\frac{60}{13}$ is $\boxed{5}$.

See Also

2008 iTest (Problems)
Preceded by:
Problem 5
Followed by:
Problem 7
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100