Question

Sarita says the equation of a line with a y-intercept of 7 that includes the point (3, -2) is y = -2 / 3 x + 7. Is she right? If so, explain why. If not, find the correct equation.

Answer 1

Sarita is wrong, the correct equation is
`y=-3x+7`

Explanation:

we know that

The equation of a line in slope intercept form is equal to

`y=mx+b`

we have

`point(3,-2)\\b=7`

substitute in the equation

`-2=m(3)+7`

Solve for m

`3m=-2-7`

`3m=-9`

`m=-3`

substitute

`y=-3x+7`

therefore

Sarita is wrong