Evaluate the expression 3x-9 if x equals 5

In the film, zeke the zombie slayer versus the zombies from space, zeke slayed 140 zombies. in the sequel, zeke the zombie slayer versus the zombies from space, part 2, he slayed 5% more zombies. how many zombies were slain by zeke in the sequel?

Need ! give step by step solutions on how to solve number one \frac{9-2\sqrt{3} }{12+\sqrt{3} } number two x+4=\sqrt{13x-20} number three (domain and range) f(x)=2\sqrt[3]{x} +1

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?