Find the distance of the line segment joining two points (4,-3) and (12,3)

Giving 100 points asap bev has to cut her grandma's grass this weekend and wants to know exactly how much area she will be cutting. calculate the area of the polygon. be sure to show all your work and explain your answer.

With finding limits of multi variable !

Write the summation to estimate the area under the curve y = 1 + x2 from x = -1 to x = 2 using 3 rectangles and right endpoints