Question

Equation to the straight line cutting off an intercept unity from the positive direction of the axis of $y$ and inclined at ${45}^o$ to the axis of $X$ is

• A. $x+y+1=0$
• B. $x-y+1=0$
• C. $x-y-1=0$
• D. $x-y+2=0$

Answer 1

The correct option is B $x-y+1=0$

REF.Image.

Angle from positive x-axis, $\theta ={45}^{\circ }$

$\Rightarrow$ slope =$\tan \theta =\tan 45=1$

From point - slope from lines

equation : $y-1=1\left(x\right)$

$\Rightarrow y=x+1\Rightarrow \left(B\right)$