1. Find the area of th quadrilateral formed by A(3, 4), B(-1, 6),
C(-3, -4), and D(6, 1).
2. The line joining (-4, 6) and (-1, -3) is perpendicular to the line joining (0, 4) and (3, a). Find a.
3. Show that x + y - 2 = 0 is perpendicular bisector of the line joining the origin and (2, 2).
4. Find the equation of the line which is concurrent with the lines y = x and y = 2 - x and perpendicular to the line y = 4x + 5.
5. If three or more parallel lines are intersected by two transversals, prove that the intercepts made by them on the transversal are proportional.
6. The bisector of the angle B and C of a triangle ABC meet the opposite sides at D and E respectively. If DE || BC, prove that the triangle is isosceles.
7. PQR is a triangle in which PQ = QR and Z is a point on the side PR such that QR2 = PR.RZ. Prove that QZ = QR.
8. If (A + B)2 = A2 + B2 and
find a and b.
9. Find Y. Given
10. Find the Standrard Deviation of the first five natural numbers.