A line passes through $(4,1),(1,y),$ and $(x,2)$. What is the value of $x$ in terms of $y$?
What equation do I have to use for this problem? $m=\frac{y_2-y_1}{x_2-x_1}$ , $y=mx+b$ , $y-b=m(x-a)$ I tried using them, but unable to find the answer, can someone please explain.
$$m=\frac{1-y}{4-1}=\frac{1-x}{4-2}$$ $$\implies \frac 13-\frac y3=\frac 12 -\frac x2$$ $$\implies 2-2y=3-3x $$ $$\implies 3x=3-2+2y=1+2y$$ $$\require{enclose}\enclose{box}{x=\frac 13(1+2y)}$$