Question

How many right triangles have a hypotenuse that measures 4x + 2 meters and legs that measure 4x-2 meters and x + 6 meters? What are the dimensions of the triangle(s)?

Answer 1

9514 1404 393

Answer:

• 2 triangles; x={2, 18}
• 10 m, 6 m, 8m
• 74 m, 70 m, 24 m

Explanation:

The given sides will form a right triangle when ...

(4x +2)² = (4x -2)² +(x +6)² . . . . . the Pythagorean theorem is satisfied

16x² +16x +4 = 16x² -16x +4 +x² +12x +36 . . . . eliminate parentheses

x² -20x +36 = 0 . . . . . simplify to standard form

(x -2)(x -18) = 0 . . . . . . factor

x = 2 or 18 . . . . . . . . values of x that make the factors zero

There are two triangles.

For x = 2

hypotenuse = 4(2) +2 = 10

leg1 = 4(2) -2 = 6

leg2 = 2 +6 = 8

dimensions are 6 m by 8 m with hypotenuse 10 m.

For x = 18

hypotenuse = 4(18) +2 = 74

leg1 = 4(18) -2 = 70

leg2 = 18 +6 = 24

dimensions are 24 m by 70 m with hypotenuse 74 m.