Given,
A straight line passes through A(9,0) and makes a angle 30∘ with the x−axis,
And it is rotated by 15∘ degree clockwise
So, the new angle with the x−axis will be θ=30∘−15∘=15∘

Hence, the equation of the line will be,
y−0=tan15∘(x−9)
⇒y=tan(45∘−30∘)(x−9)
⇒y=1+311−31(x−9)
⇒y=(2−3)(x−9)