Question

What is the equation of the line between `(-11,12)` and `(7,-7)`?

Answer 1

`y=-19/18x+7/18`

Explanation:

`"the equation of a line in "color(blue)"slope-intercept form"` is.

`•color(white)(x)y=mx+b`

`"where m is the slope and b the y-intercept"`

`"to calculate m use the "color(blue)"gradient formula"`

`•color(white)(x)m=(y_2-y_1)/(x_2-x_1)`

`"let "(x_1,y_1)=(-11,12)" and "(x_2,y_2)=(7,-7)`

`rArrm=(-7-12)/(7-(-11))=(-19)/18=-19/18`

`rArry=-19/18x+blarrcolor(blue)"is the partial equation"`

`"to find b substitute either of the 2 given points into"`
`"the partial equation"`

`"using "(-11,12)" then "`

`12=209/18+brArrb=216/18-209/18=7/18`

`rArry=-19/18x+7/18larrcolor(red)"equation of line"`