Solve for value the two angles in the triangle and classify the triangle using the sides and angles

What is the point-slope form of the equation for the line with a slope of -2 that passes through (1,4)?

Aboat costs 19200 and decreases in value by 12% per year. how much will it cost in 5 years

1- 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. 2- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis. 3- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in part b?