Problema Solution
A coin of circle shape has a radius of 3 cm with a square of side x cm removed from its center. The area of each face of the coin is 7(pi) cm2.
Form an equation in x and solve the equation.
Answer provided by our tutors
Let
R = 3 cm the radius of the circle
A = 7pi cm^2 the area of the face of the coin
A1 = area of the circle
A2 = x^2 area of the square
A = A1 - A2
The area of the circle is:
A1 = R^2*(pi)
A1 = (3)²(pi)
A1 = 9(pi) cm²
If we plug the value for the areas into A = A1 - A2 we get:
9(pi) - x^2 = 7(pi)
If we solve the above equation with pi = 3.14, then we get,
x=√6.28
x =2.506 cm approximately