Question

I need help completing a problem please.

Write an equation in slope-intercept form fro the line (-7,0), (0,-7)

So far, I have completed...............
y=mx+b
m= -7-0/0-7 = -7/-7 = 1

Therefore, now in order to find the equation, I think i should be using y-y1=m(x-x1)....is that correct? If so, would it be like

y-0=m(x-(-7)
Which would be y=x-7

I do not think i'm doing it completely correct..

Answer 1

that's not correct
your problem come from the slope
m= -7-0/0-7 = -7/-7 = 1 <= it's wrong
m=(ya-yb)/(xa-xb)=(0-(-7))/(-7-0)=-1 !and not 1

Answer 2

Your m value is wrong.
\[m= {-7-0 \over 0-(-7) } = {-7 \over 7} = -1\]

Answer 3

Nice, i see where I made that mistake. When I did my problem, I did 0-7 and not 0-(-7); big difference. Thank you so much for catching that. So, would it be completed by putting
y-0=m(x-(-7) and equal the 7

Answer 4

y-0=m(x-(-7) <= that's not correct

Once you get the slope you have to solve this equation using one of the point
y=mx+b
y=-x+b
0=-(-7)+b
b=-7

so y=-x-7
Now check your answer with the other point
(-7,0)
y=-7 and -x-7=-0-7=-7 => correct!