Question

(5,-10) and (15,-20). find the equation of this line.

Answer 1

y = -x - 5.

Explanation:

The slope of the line is (-20-(-10) /(15-5)

= -10/10 = -1.

Now use the point slope form of a straight line:

y - y1 = m(x - x1) where m = the slope and (x1, y1) is a point on the line.

So we have:

y - (-10) = -1(x - 5)

y + 10 = -x + 5

y = -x + 5 - 10

y = -x - 5.

Answer 2

y = -x-5

Explanation:

slope of the line is =(-20+10) / (15-5) = -10/10 = -1

Now equation of line is y+10=(-1)(x-5)

i.e. y+10= -x +5

i.e y = -x-5