Write an equation for the line through P (2, -1) with slope m = 4.
A) 4x - y - 9 = 0
B) y = 4x + 9
C) 4x + y = 7
D) y = 2x - 5
E) y = 2x + 5

Question

Quizplus · Accepted Answer

The equation of a line with slope $m$ and passing through a point $(x_1, y_1)$ is given by $y - y_1 = m(x - x_1)$. Substituting $m = 4$, $x_1 = 2$, and $y_1 = -1$ gives $y + 1 = 4(x - 2)$, which simplifies to $4x - y - 9 = 0$.

Write an Equation for the Line Through P (2, -1)