Question

How do you write an equation in slope intercept form given (2, 1) and has slope 3?

Answer 1

`y=3x-5`

Explanation:

Standard format of the equation is `y=mx+c`

Where the slope is `m=3` giving:

`" "y=3x+c`

We are told that the straight line graph passes through the point

`" "(x,y)->( 2,1)`

So by substitution you end up with:

`" "y=3x+c" becomes "1=3(2)+c`

`" "1=6+c`

Subtract 6 from both sides giving

`" "-5=c`

So the equation is

`" "y=3x-5`

Answer 2

y = 3x - 5

Explanation:

Begin by writing in the form : y - b = m(x - a) , the standard form for the equation of a straight line.
In this form . m = gradient(slope) and (a,b) , a point on the line.

here m = 3 and (a,b) = (2,1)

hence : y - 1 = 3(x - 2 ) → y - 1 = 3x - 6

in slope-intercept form y = 3x - 5