find the equation of a line that goes through points (2,4) and (6,8)

Question

anonymous · Answer

To find the equation of a line you need a point it passes through and it's gradient. to get the gradient you use the formula $$\frac{ y_{2}-y_{1}}{ x_{2}-x_{1} }$$
Which comes out to be$$\frac{ 8-4 }{ 6-2 } = \frac{ 4 }{ 4 } = 1$$
Now we know the gradient you can put it all in the formula for any general line$$y-y_{1}=m(x-x _{1})$$

So using the point 2,4, $$y-4=1(x-2) -> y-4=x-2 -> y=x-2+4 -> y=x+2$$

Which is the answer in y=mx+c form :D

anonymous · Answer

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can you find the slope of this line?

anonymous · Answer

That is not my question

anonymous · Answer

Can somebody please answer what are the 3 possible points you can use to graph y= 3-x

anonymous · Answer

When x = 0 is the first point
so y = 3-0 y = 3. So the first point is (0,3)

Second is when y = 0

0= 3-x, x=3 so the second is (3,0)

Because the line is a straight line all you need is two points and draw a line through them with a ruler. If you really need a third point just read one off the line :)