Isosceles Right Triangle Dimensions: Solving for Side Lengths with Area 32

Question

In front of you is an isosceles right triangle.

The expressions listed next to the sides describe their length.

( x>-8 length measurements in cm).

Since the area of the triangle is 32.

Find the lengths of the sides of the triangle.

323232x+8x+8x+8

Video Solution

Solution Steps

00:00 Find the lengths of the triangle's sides
00:03 We'll use the formula for calculating triangle area
00:07 (height times side) divided by 2
00:12 Sides are equal according to the given data
00:15 We'll substitute the area value according to the given data
00:25 We'll multiply by the denominator to eliminate the fraction
00:32 Taking the square root, remember we get 2 solutions
00:35 One positive and one negative
00:40 We'll isolate the unknown and find the solution for each possibility
00:46 This is one solution, but it doesn't fit the domain
00:53 This is the second solution, we'll substitute to find the sides
00:59 And this is the solution to the question

Step-by-Step Solution

To solve this problem, we'll utilize the properties of an isosceles right triangle and the area formula:

  • Step 1: Identify the expression for the legs of the triangle as x+8 x + 8 .
  • Step 2: Use the area formula for a right triangle, 12×(leg)2=32 \frac{1}{2} \times (\text{leg})^2 = 32 .
  • Step 3: Given that the triangle is isosceles, solve for x x by substituting and expanding the terms.
  • Step 4: Derive the hypotenuse using the known leg value and calculate leg×2 \text{leg} \times \sqrt{2} .

Now, let's work through each step:

Step 1: Recognize both legs of the isosceles triangle are x+8 x + 8 .

Step 2: Apply the area formula for right triangles:
We know 12×(leg)×(leg)=32 \frac{1}{2} \times (\text{leg}) \times (\text{leg}) = 32 . Therefore, the equation is:

12×(x+8)2=32 \frac{1}{2} \times (x + 8)^2 = 32

Step 3: Simplify and solve for x x .

(x+8)2=64(x + 8)^2 = 64 x+8=64x + 8 = \sqrt{64} x+8=8orx+8=8x + 8 = 8 \quad \text{or} \quad x + 8 = -8

Given the constraint x>8x > -8, we discard x+8=8x + 8 = -8 since it violates the condition. Therefore,

x+8=8x + 8 = 8 x=0x = 0

Recalculate x+8 x + 8 , which states the leg is 8.

Step 4: Determine the hypotenuse.

hypotenuse=82hypotenuse = 8\sqrt{2}

Therefore, the side lengths of the triangle are 8,8,82 8, 8, 8\sqrt{2} . Match this to the choices given, which is option 3.

The lengths of the sides of the triangle are 8,8,82 8, 8, 8\sqrt{2} .

Answer

8,8,82 8,8,8\sqrt{2}