What is the value of a2 – b2 if a + b = 6 and a – b = –3?

Choose the correct slope of the line that passes through the points (1, -3) and (3, -5)

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

Simplify 1/3 12x - 6 a. -2x-1 b.-2x-8 c.-x+4 d.3x+10 e. 4x-2