In a parallelogram a diagonal of the length 20cm is perpendicular to one of the sides. Find the longer side of parallelogram if its perimeter is 80cm

Which of the following is the explicit rule for a geometric sequence defined a recursive formula of a -5a for which the first term is 23?

If cos(2x) = tan^2(y), show that cos(2y) = tan^2(x).

Jane’s favorite fruit punch consists of pear, pineapple, and plum juices in the ratio 5: 2: 3. how many cups of pear juice should she use to make 20 cups of punch?