How do you get the quadratic equation of (1,2)

Complete the steps, which describe how to find the area of the shaded portion of the circle. find the area of the sector by multiplying the area of the circle by the ratio of the to 360. subtract the area of the triangle from the area of the sector.

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Molly shared a spool of ribbon with 12 people. each person received 3 feet of ribbon. which equation can she use to find r, the number of feet of ribbon that her spool originally had?