What should be added to x^2 + 4 to get 2x^2 + 5

An initial investment of $100 is now valued at $150. the annual interest rate is 5%, compounded continuously. the equation 100e0.05t = 150 represents the situation, where t is the number of years the money has been invested. about how long has the money been invested? use your calculator and round to the nearest whole number. years

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

Factor the polynomial by its greatest common monomial factor.