Question

If the slope of a line is -2 and it passes through thepoints (x, 4) and (-2,10). What is the missing xvalue?

Answer 1

If a line with slope m passes through points with coordinates (x,y) and (x1, y1), the equation can be written as,

$\frac{y_1-y}{x_1-x}=m$

Here,

$\begin{gathered} m=-2 \\ (x,y)=(x,4) \\ (x_1,y_1)=(-2,10) \end{gathered}$

Substitute these values in the above equation to calculate the value of x.

$\begin{gathered} \frac{10-4}{-2-x}=-2 \\ \frac{6}{-2-x}=-2 \\ 6=-2(-2-x) \\ \frac{6}{-2}=-2-x \\ -3=-2-x \\ -3+2=-x \\ -1=-x \\ 1=x \end{gathered}$

Therefore, the value of x is 1.