Circumference of a circle is found with the equation
C = 2 × pi × r
where r is the radius. So for your problem...
C = 2 × 3.14 × 4
C = 25.12 meters
1/10 * 0.08 = 0.08 * 0.1 = 0.008
R=d/2 is the answer to this
Y=210-7X you have $210 and want to know how many books she can buy with that money.
Angle A and angle B sums up to 180 (interior angles)
6x - 35 + 3x + 53 = 180
9x + 18 = 180
9x = 162
x = 18
angle A = 6(18)-35 = 73 degrees
