First of all we need to find the slope using this formula :
Slope = [ y(A) - y(B) ] ÷ [ x(A) - x(B) ]
Suppose that :
A = ( 1 , 0.6 )
&
B = ( - 9 , - 3.4)
Thus :
Slope = [ 0.6 - ( - 3.4) ] ÷ [ 1 - ( -9 ) ]
Slope = [ 0.6 + 3.4 ] ÷ [ 1 + 9 ]
Slope = 4 ÷ 10
Slope = 4/10 = 2/5
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Now it's time to find the equation , to do that we just have to use the point-slope form formula of the linear equation which is like this :
y - y( A or B ) = Slope × ( x - x( A or B) )
We're almost done; just need to put the coordinates of point A or point B and the Slope to find the equation :
I'm gonna use A for it but you can do that with B , They will give same equation.
y - 0.6 = 2/5 × ( x - 1 )
y - 0.6 = 2/5 x - 2/5
y - 6/10 = 2/5 x - 2/5
y - 3/5 = 2/5 x - 2/5
Add both sides 3/5
y - 3/5 + 3/5 = 2/5 x - 2/5 + 3/5
y = 2/5 x + 1/5
And we're done ...