Find the value of the variables

Which formula gives the area of a triangle? a=1/2(b+h)

The triangles are similar. what is the value of x? show your work.

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