(High points) please solve with explanation I’ve been asking all day

Simplify 15(x - 4)(x -1)-3(x + 4)(x - 1) with steps

Write an inequality and solve each problem.for exercises 11 and 12, interpret the solution.

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.