Answer:
x = 6
Step-by-step explanation:
The formula of slope of a straight line passing through two given points ([tex]x_{1},y_{1}[/tex]), and ([tex]x_{2},y_{2}[/tex]) is given by
[tex]m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}[/tex].
As, the straight line passes through the points (x,-4) and (2,8) and has slope - 3.
So, we can write [tex]\frac{8 - (- 4)}{2 - x} = - 3[/tex]
⇒ 12 = 3x - 6
⇒ 3x = 18
⇒ x = 6 (Answer)
