Question

If a straight line passes through the points $\left( \frac{-1}{2},1 \right)$ and $(1, 2)$, then its $x$-intercept is

• A. $-2$
• B. $-1$
• C. $2$
• D. $1$

Answer 1

Answer: (A)

$-2$

Answer 2

The equation of straight line passing through the points $\left( -\frac{1}{2},1 \right)$ and (1, 2) is $(y-{{y}_{1}})=\frac{{{y}_{2}}-{{y}_{1}}}{{{x}_{2}}-{{x}_{1}}}(x-{{x}_{1}})$
$\Rightarrow$ $(y-1)=\frac{2-1}{1+\frac{1}{2}}\left( x+\frac{1}{2} \right)$
$\Rightarrow$ $(y-1)=\frac{2}{3}\left( x+\frac{1}{2} \right)$
$\Rightarrow$ $3(y-1)=(2x+1)$
$\Rightarrow$ $2x-3y=-4$
$\Rightarrow$ $\frac{x}{-2}=\frac{y}{\left( \frac{4}{3} \right)}=1$ So, the x-intercept is $-2$ .