Question

The point (3,-1) is on the line by which equation below?

Answer 1

D. y = x - 4

Explanation:

Given the following data;

Points (x, y) = (3, -1)

To find the equation of line;

First of all, we would determine the slope of the graph.

Mathematically, slope is given by the formula;

`Slope = (Change \; in \; y \; axis)/(Change \; in \; x \; axis)`

`Slope, m = \frac {y_(2) - y_(1)}{x_(2) - x_(1)}`

Substituting into the equation, we have;

`Slope, m = \frac {5 - 5}{5 - 5}`

Slope, m = 1

Generally, the equation of straight line is y = mx + c

Where;

m is the slope.

x and y are the points

c is the intercept.

Substituting the values in order to find the intercept, we have;

Using points (x, y) = (3, -1)

-1 = 1*3 + c

-1 = 3 + c

c = -1 - 3

Intercept, c = -4

Therefore, the equation of line becomes;

y = x - 4.