How do I solve 8, 9, and 10?
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Answer:
8)
[tex]y-8=m(x+6)\\y-8=\frac{-4}{3}(x+6)\\\\y=\frac{-4}{3}x[/tex]
9)
[tex]y+4.5=mx\\y=15x-4.5[/tex]
10)
[tex]y+1=m(x-1)\\y=-2(x-1)-1\\y=-2x+1[/tex]
Step-by-step explanation:
We can use the definition of a line:
[tex]y-y_0=m(x-x_0)[/tex]
where [tex]y_0[/tex] and [tex]x_0[/tex] co-ordinates of a point on that line, and where [tex]m[/tex] is the gradient of the line.
We can work out the gradient of the line by looking at the differential, or the change in y compared to the change in x.
[tex]m=\frac{\Delta y}{\Delta x} = \frac{y_1-y_0}{x_1-x_0}[/tex]
where [tex](x_0,y_0)[/tex] and [tex](x_1,y_1)[/tex] are two distinct points on the line.
You now have the tools needed to go about answering these questions!