A student states that a triangle can be formed with side lengths 4 in, 5 in, and 8 in. Is the student correct? Why, or why not?

A. Yes, because [tex][tex]$4+5\ \textgreater \ 8$[/tex][/tex]
B. Yes, because [tex][tex]$5+8\ \textless \ 4$[/tex][/tex]
C. No, because [tex][tex]$4+5\ \textgreater \ 8$[/tex][/tex]
D. No, because [tex][tex]$5+8\ \textgreater \ 4$[/tex][/tex]



Answer :

To determine whether a triangle can be formed with side lengths 4 inches, 5 inches, and 8 inches, we can use the Triangle Inequality Theorem. This theorem states that for any three side lengths to form a triangle, the sum of the lengths of any two sides must be greater than the length of the remaining side.

Let's apply the Triangle Inequality Theorem step by step:

1. Check if the sum of the first two sides is greater than the third side:
[tex]\[ 4 + 5 > 8 \][/tex]
[tex]\[ 9 > 8 \quad \text{(True)} \][/tex]

2. Check if the sum of the first and third sides is greater than the second side:
[tex]\[ 4 + 8 > 5 \][/tex]
[tex]\[ 12 > 5 \quad \text{(True)} \][/tex]

3. Check if the sum of the second and third sides is greater than the first side:
[tex]\[ 5 + 8 > 4 \][/tex]
[tex]\[ 13 > 4 \quad \text{(True)} \][/tex]

Since all three conditions of the Triangle Inequality Theorem are satisfied, we can conclude that a triangle can be formed with side lengths 4 inches, 5 inches, and 8 inches.

Therefore, the student is correct, and the correct justification is:
"Yes, because [tex]\(4 + 5 > 8\)[/tex]."