Why does 2 plus 2 = 4 but not 5

Consider the line y = -3/-2 x +6. find the equation of the line that is perpendicular to this line and passes through the point (-9,-3). find the equation of the line that is parallel to this line and passes through the point (-9,-3).

Which of the following contains a variable?

Which of the following is the best first step in solving the equation below? 4+2㏒³x=17