Four times a number +15 is equal to two times the same number +45. What is the number?

Polynomial that can be factored as (3x-4)(3x+4)

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)

The holiday party will cost $160 if 8 people attend. if there are 40 people who attend the party, how much will the holiday party cost