I really don't get it plz help

Ab and bc form a right angle at point b. if a= (-3,-1) and b= (4,4) what is the equation of bc?

Elizabeth claims that the fourth root of 2 can be expressed as 2^m since (2^m)^n = 2. find the values of m and n for the case where elizabeth's claim is true.

In an equilateral triangle, each angle is represented by 5y+3. what is the value of y? a. 9.7 b. 10.8 c. 11.4 d. 7.2