Question

10^(x+2) - 10^(x)=9900
solve for x

Answer 1

Answer:

n=10

Step-by-step explanation:

Write n(n+1)(n-1)=990=11*9*10

See that (n-1)(n)(n+1) are 3 consequtive integers. and the prome factorization of 990 yeilds 9*10*11

n=10

Answer 2

Answer:

x=2

Step-by-step explanation:

10^(x+2) - 10^x = 9900

Taking 10^x in common on left side

10^x(10^2 -1) = 9900

10^x(99) = 9900

dividing 99 on both sides

10^x =100 = 10^2

so x=2