We go from 10x+20 = 50 to 10x = 30 after we subtract 20 from both sides. So we use the subtraction property (of equality).
Answer: Choice D
Answer:
b = 15
Step-by-step explanation:
Solve for b:

Cross multiply:

The area is 11.61 square feet and the perimeter is 14 feet. i hope this helps :)
Area=Length times width
Perimeter=Length+Length+width+width