Δ FCD is a right triangle ( 3² + 4² + 5² ).
10 : EB = 5 : 3
5 EB = 30
EB = 6
With Pythagorean theorem:
CE² = 10² - 6² = 10 - 36 = 64
CE = 8
ED = 5
AB = 2 · 5 = 10
Answer: The length of the side AB is 10.
#21)
<span>Using Pythagorean Theorem a^2 + b^2 = c^2
so
</span>a^2 = c^2 - b^2
x^2 = 42^2 - 38^2
x^2 = 1764 - 1444
x^2 = 320
x =√320
x = √(64 * 5)
x = 8√5
3.69/3=
1.23
Hope this helps! :)
Thank it is c and if not l am sorry