Question

Find the equation of straight line whose angle of inclination is ${45}^o$ and y-intercept is $\frac{2}{5}$.

Answer 1

Slope of the line, $m=\tan \theta$
$=\tan {45}^o=1$
y-intercept is $c=\frac{2}{5}$
By the slope-intercept form, the equation of the straight line is
$y=mx+c$
$=x+\frac{2}{5}\Rightarrow y=\frac{5x+2}{5}$
$\therefore$ The equation of the straight line is $5x-5y+2=0$