If the nth term of a sequence is 5x4n-1 find the 3rd term

Toyland is having a sale. all items are 20% off. how much will you save on an item that usually sells for 95$ explain your

Plzzz plzz maths ! quadratic sequences =an^2+bn 1) 1,6,15,28,45 2)5,18,39,68,105 3) 1,8,21,40,65 4) 7,24,51,88,135 5) -1,2,9,20,35

Which expression is equivalent to 2x^2+7x+4?