Question

Line QR goes through points Q(0, 1) and R(2, 7). Which equation represents line QR?

Answer 1

To determine the equation of the line using two points, calculate first the slope with the equation,
                                            m = (y2 - y1)/ (x2 - x1)
In this given, 
                                            m = (7 - 1)/ (2 - 0) = 3

Use the point-slope form of the equation where,

                                               y - y2 = m (x - x2)

                                           y - 7 = 3 (x - 2), y = 3x + 1

Thus, the equation of the line is y = 3x + 1