Write an equation in slope intercept form for the line with slope -3 and Y intercept one

The sum of two numbers is 12 and their difference is 18 what are the two numbers

What set does not contain -3 the set of all real numbers the set of all integers the set of all whole numbers the set of all rational numbers

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.