If triangle is formed including point ' P ' the other points must be one from l1 and other point from l2. Number of triangles formed with P, n(E1)=‌3C1×‌5C1=15‌ ways ‌ When P is not included, Number of triangles formed n(E2)‌=‌3C2×‌5C1+‌3C1×‌5C2 ‌=15+15=30 Total number of triangle =n(E1)+n(E2) =15+30=45