How long is the hypotenuse of a right triangle whose legs measure [tex]$3x$[/tex] and [tex]$4x$[/tex] ([tex]x \ \textgreater \ 0[/tex])?

A. [tex][tex]$7|x|$[/tex][/tex]
B. 5
C. [tex]$5x$[/tex]
D. [tex]$7x$[/tex]
E. None of these



Answer :

To determine the length of the hypotenuse of a right triangle whose legs measure [tex]\(3x\)[/tex] and [tex]\(4x\)[/tex] (with [tex]\(x > 0\)[/tex]), we can employ the Pythagorean theorem. The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse ([tex]\(c\)[/tex]) is equal to the sum of the squares of the lengths of the other two sides ([tex]\(a\)[/tex] and [tex]\(b\)[/tex]). The formula is:

[tex]\[ c^2 = a^2 + b^2 \][/tex]

Here, [tex]\(a = 3x\)[/tex] and [tex]\(b = 4x\)[/tex]. Let's follow these steps to find the hypotenuse [tex]\(c\)[/tex]:

1. Square the lengths of the legs:
[tex]\[ (3x)^2 = 9x^2 \][/tex]
[tex]\[ (4x)^2 = 16x^2 \][/tex]

2. Sum the squares of the legs:
[tex]\[ 9x^2 + 16x^2 = 25x^2 \][/tex]

3. Take the square root of the sum to find the hypotenuse:
[tex]\[ c = \sqrt{25x^2} \][/tex]

4. Simplify the square root:
[tex]\[ c = \sqrt{25} \cdot \sqrt{x^2} \][/tex]
[tex]\[ c = 5 \cdot |x| \][/tex]

Since [tex]\(x > 0\)[/tex], [tex]\(|x| = x\)[/tex], so the hypotenuse [tex]\(c\)[/tex] simplifies to:
[tex]\[ c = 5x \][/tex]

Therefore, the length of the hypotenuse of the right triangle is given by [tex]\(5x\)[/tex]. The correct answer is:

C) [tex]\(5x\)[/tex]