(2,-5), m=2

Question

I don't understand my math

Answer 1

Just to add to Nataliya's anwer. The set of numbers given identify a point on the coordinate grid, and the m represents the slope of a line on which the identified point lies. So if you were to graph this line, you would start at (2, -5) then move 2 up and 1 to the right (slope is always rise over run so a slope(m) of 2 is really 2/1).

There are two equations your teacher might want you to use to "name" the line. Slope-intercept (or y-intercept) as Nataliya described below is usually written y=mx+b. The simplest way to write this equation when given a point and a the slope of a line is to plug your known values into this equation. SO..

You know the coordinates of one point (you can plug those into your x and y) and you know the slope (that goes int the m space). It will look like this:

-5=2(2)+b -------Now we will solve for b. First multiply the 2s

-5=4+b ----------Next we will subtract 4 from each side to allow the variable(b) to stand alone.

-4  -4

-9=b---------------- Now, we use our slope and y intercept(the -9, or b) and replace them into the equation, leaving y and x as variables....

y=2x-9

I hope that helps you understand these kinds of questions a little better!

Answer 2

As I understood, you have to write the slope-intercept form of linear equation.
m = (y₂ - y₁)/(x₂ - x₁) ----> (y - (-5))/(x - 2) =2 ----> y + 5 = 2(x - 2)
y = 2x - 4 - 5 ----> y = 2x - 9