Question

How do you write an equation of a line given slope -3 and passes through (5,2)?

Answer 1

`y=-3x+17`

Explanation:

The general formula for a line is `y=mx+c` where `m=` gradient and `c=` the `y` intercept.

Using the numbers you have been given in the question, you can put these numbers into the general formula to calculate `c`.

The gradient is -3
From the coordinates given, the `x` is 5 and `y` is 2.

`2=-3*5+c`

`2=-15+c`

`c=17`

Now you have worked out the value of `c`, (the `y` intercept), you can give the equation of the line, by inserting `-3` in place of the `m` and `17` in place of the `c`:

`y=-3x+17`