Question

How do you write an equation in standard form for a line passing through(–2, 1) and (4, 13)?

Answer 1

The equation is : `y = 2x + 5`

Any linear function has the following form : `y = mx + b`

Firstly, you need to find the slope `m` of your line.

It is given by :

`m = (y_2-y_1)/(x_2-x_1)`,

where `(x_1,y_1)=(-2,1)` and `(x_2,y_2) = (4,13)` or vice versa.

So `m = (13-1)/(4+2) = 2`.

Then, in order to find `b`, you have to solve the following equation :

`y_1 = mx_1 + b` or
`y_2 = mx_2 + b`

So `1 = 2*(-2) + b => b = 5`

Now you have the equation of your line :

`y = 2x + 5`