Prove that if d|m and d|n, then d|(m+n)

Kapil needed to buy a long wooden beam. he went to two sawmills that each charge an initial fee plus an additional fee for each meter of wood. the following equation gives the price (in dollars) of a wooden beam from the first sawmill as a function of its length (in meters). p = 5+20xp=5+20x

The trigonometric ratios sine and secant are reciprocals of each other

How do i multiply two digit numbers