How to prove it's an identity
sin y + sin 3y + sin 5y + sin 7y = 4 cos y cos 2y sin 4y

Solve each quadratic equation by factoring and using the zero product property. x^2 - 8x + 30 = 3x

You have a square piece of cardboard that measures 14 inches on each side. to build a box, you cut congruent squares out of each corner of the cardboard. use the picture to find the area of the cardboard you were used to build the box

Many newspapers carry a certain puzzle in which the reader must unscramble letters to form words. how many ways can the letters of emdangl be arranged? identify the correct unscrambling, then determine the probability of getting that result by randomly selecting one arrangement of the given letters.