Question

The equation of the line passing through the points (-1, 8) and (3, 16) can be expressed as y = mx + b. Give the value of b.

Answer 1

To, find b, let us find m first

Formula of slope, m=
`(y2-y1)/(x2-x1)`

where, (x1,y1)=(-1,8) and (x2,y2)=(3,16)

m=
`(16-8)/(3-(-1)) =(8)/(3+1) =(8)/(4) =2`

m=2

Plugging m=2 and (x,y)=(-1,8) in y=mx+b

8=2*-1+b

8=-2+b

Adding 2 on both sides

b=10