Find Sg for a geometric series for which a1=81 and r =1/9

Aline parallel to a triangle's side splits ab into lengths of x - 5 and x + 2. the other side, ac, is split into lengths of x and x + 12. what is the length of ac? a) 12 b) 24 c) 36 d)

What is 32+4 x (16 x 1/2) -2 show your work}

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.