find the value of r so that the line through (2,-3) and (-4,r) has a slope of -1/2 | please explain steps

What percent of the circle below is shaded?

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6

Quadrilateral abcd is a parallelogram with diagonals that intersect at point e. which of the following statements is true?