Answer:
Step-by-step explanation:
(25x-5) 12X- Ax15
and means + or addition
so 10x+7+x
11x+7
Answer: The missing length is 40 m.
30^2 + b^2 = 50^2
900 + b^2 = 2500
-900 -900
b^2 = 1600
b= 40