Question

Given the points ( − 7 , − 9 ) and ( 0 , 3 ) on a line, find its equation in the form y = m x + b .

Answer 1

`y = (12)/(7) x + 3`

Explanation:

y=mx +b

m refers to the gradient of the line,

b refers to the y intercept

gradient formula=
`(y1 - y2)/(x1 - x2)`

`m = (3 - ( - 9))/(0 - ( - 7)) \\ m = (3 + 9)/(7) \\ m = (12)/(7)`

substitute the value of m into the equation:

`y = (12)/(7) x + b`

y-intercept occurs at x=0.

Given the point (0,3), we know that the y-intercept of the line is 3.

Thus, the equation of the line is
`y = (12)/(7) x + 3`