# find the locus of point of intersection of the lines xcosA+ysinA=a and xsinA-ycosA=b, where A is variable

Squaring and adding we get x

^{2}+ y

^{2}= a

^{2}

^{ }+ b

^{2}

^{ }

Hence it is a circle with origin as centre and (a

^{2}

^{ }+ b

^{2})

^{1/2}as radius