Answer:
7.) 16.7
Step-by-step explanation:
7). First you have to find the length of the line with the triangle that is at a 90 angle with the longest side of the triangle
Using the pythagrorem theorem a² + b² = c²
4² + b² = 5²
b² = 5² - 4²
b² = 25 - 16
b² = 9
√b² =√9
b = 3
next you do the same thing to find the missing segment of the longest side
3² + b² = 13²
b² = 169 - 9
b² = 160
b = √160 or ≈ 12.7
12.7 + 4 = 16.7
so 16.7 is the length of that side
