50 POINTS !!
PLEASE HELP !! ILL GIVE BRAINLIEST TO THE RIGHT ANSWERS.

Answer:
8.987mm
Step-by-step explanation:
a² + b² = c²
7.4² + 5.1² = c²
54.76 + 26.01 = 80.77
Take the square root of 80.77, and you have the answer: 8.987mm
Hope this helps :)