Answer:
20
Step-by-step explanation:
3x + x + 100 = 180 (sum of angles on a straight line)
4x = 180-100
4x=80
divide both sides by 4
x=20
Answer:
It is a solution
Step-by-step explanation:
Given

Required
Determine if
is a solution
implies that:


To check if it is a solution, we simply substitute values for x and y in the given equation;




Since both sides of the equation are equal; then, Yes, it is a solution
Answer:
8
Step-by-step explanation:
A circular pool with a diameter of 18 ft will have a uniform
4 ft concrete walkway poured around it. If the concrete cost $4.25 a square
foot, how much will it cost for the concrete?
This can be solve be solving the area of walkway
Area of walkway is equal to = (pi)( 9 ft +4) ^2– (pi)(9ft)^2
= 276.46 sq ft
Cost = 276.46 sq ft * ($4.25 a square foot) = $1174.70