A triangle has side lengths of [tex](q + r)[/tex] centimeters, [tex](5q - 10s)[/tex] centimeters, and [tex](5s - 7r)[/tex] centimeters. Which expression represents the perimeter, in centimeters, of the triangle?

A. [tex]-16rs + 11qs[/tex]
B. [tex]-2rs + 2qr - 5qs[/tex]
C. [tex]6q - 6r - 5s[/tex]
D. [tex]6q - 2s - 9r[/tex]



Answer :

To determine the expression that represents the perimeter of the triangle, we need to add together the lengths of its three sides. The given side lengths are:

1. [tex]\( q + r \)[/tex] centimeters
2. [tex]\( 5q - 10s \)[/tex] centimeters
3. [tex]\( 5s - 7r \)[/tex] centimeters

Next, we need to find the sum of these three expressions:

[tex]\[ (q + r) + (5q - 10s) + (5s - 7r) \][/tex]

Let's combine like terms step-by-step:

1. Combine all the terms involving [tex]\( q \)[/tex]:
[tex]\[ q + 5q = 6q \][/tex]

2. Combine all the terms involving [tex]\( r \)[/tex]:
[tex]\[ r - 7r = -6r \][/tex]

3. Combine all the terms involving [tex]\( s \)[/tex]:
[tex]\[ -10s + 5s = -5s \][/tex]

Putting it all together, we get the final simplified expression for the perimeter:

[tex]\[ 6q - 6r - 5s \][/tex]

Thus, the expression that represents the perimeter of the triangle is:

[tex]\[ 6q - 6r - 5s \][/tex]

Therefore, among the provided answer choices, the correct one is:

[tex]\[ \boxed{6 q - 6 r - 5 s} \][/tex]