Question 1136642
the slope of a line is -2 and the line contains the points (7 4) and (x 12) what is the value of x?
:
We can use the slope equation: m = {{{((y2-y1))/((x2-x1))}}} 
where:
x1 = 7; y1 = 4
x2 = x; y2 = 12
m = -2
:
-2 = {{{((12-4))/((x-7))}}} 
-2(x-7) = 8
-2x + 14 = 8
-2x = 8 - 14
-2x = -6
x = -6/-2
x = +3
:
:
Check
{{{((12-4))/((3-7))}}} = {{{8/(-4)}}} = -2