Answer:
x = 10
Step-by-step explanation:
2(1+5x)-3x=72
Distribute
2 + 10x -3x = 72
Combine like terms
2+7x=72
Subtract 2 from each side
2+7x-2 = 72-2
7x = 70
Divide by 7
7x/7 = 70/7
x = 10
1)
Area of largest circle - 2 * Area of one smaller circle = Area of the shaded region
AE = diameter of large circle = 48cm
radius of larger circle = diameter / 2 = 48cm / 2 = 24cm
4 circles fit across the diameter of the circle, so the diameter of the larger circle = 4 * diameter of the smaller circle
diameter of larger circle = 48cm = 4 * diameter of the smaller circle
diameter of the smaller circle = 48cm / 4 = 12cm
radius of smaller circle = diameter / 2 = 12cm / 2 = 6cm
Area of a circle = pi * r^2
Now plug the circle area equation into the first equation:
2)
Area of the shaded region = 2/7 * Area of the smaller circle
Area of the unshaded region = Area of larger circle + Area of smaller circle - Area of shaded region * 2