Question

Complete the equation of the line through (-6, -5) and (-4, -4). Use exact numbers

Answer 1

In general the equation through (a,b) and (c,d) is

`(y-b)(c-a)=(x-a)(d-b)`

Can you see that this is a line and that both (a,b) and (c,d) are on it?

Here we're given (a,b)=(-6,-5) and (c,d)=(-4,-4)

`(y- -5)(-4 - -6) = (x - -6)(-4 - 5)`

`2(y+5)=x+6`

`2y + 10 = x + 6`

`x - 2y = 4`

`y = \frac 1 2 x - 2`

Either of the last two are fine answers.