Cos(A+60°) * cos(A-60°) - sin(A+60°) * sin(A+60°) = cos2A

Solve the system by the elimination method. 3x - 2y - 7 = 0 5x + y - 3 = 0 to eliminate y, the lcm is 2. which of the following is the resulting equations? 1.3x - 2y - 7 = 0 5x + y - 3 = 0 2.3x - 2y - 7 = 0 -10x - 2y + 6 = 0 3.3x - 2y - 7 = 0 10x + 2y - 6 = 0

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

Aflagpole broke in a storm. it was originally 8 1 81 feet tall. 2 8 28 feet are still sticking straight out of the ground, where it snapped, but the remaining piece has hinged over and touches the ground some distance away. how far away is the end of the pole from the base of the pole along the ground?