Question

Write the equation of line through (3,6) and (-4,-1)

Answer 1

y=x+3

Explanation:

The slope of a line passing through the two points P = (x1, y1)and Q = (x2, y2) is given by

m= (y2-y1)/(x2-x1)

We have that x1= 3, y1= 6, x2= - 4, y2= - 1

so m = 1

Now, the y-intercept is b=y1-mx1 (or b=y2-mx2, the result is the same).

b=6-(1)(3)

b=3

Finally, the equation of the line can be written in the form

y = mx+b

y=x+3