Is 5 a irrational number

Given the equation f(x)=a(b)x where the initial value is 40 and the growth rate is 20% what is f(4)

Consider circle o, where and . m∠bpd °. °.

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?