`bar(AB) and bar(DC)` are two parallel lines and a transversal l ,intersects `bar(AB)` at P and `bar(DC)` at R . Prove that the bisectors of the interior angles form a rectangle .

overset(harr)("AB ") and overset(harr)("DC ") are two parallel lines and a transversal l, intersects overset(harr)("AB ") at P and overset(harr)("DC ") at R. Prove that the bisectors of the interior angles form a rectangle.

If in DeltaABC bar(BX) and bar(CY) are bisectors to the base angles then angleBXC =

ABCD is a rectangle. bar(AC) and bar(BD) are diagonals. Write the pairs of parallel lines, perpendicular lines and intersecting lines from the figure in symbolic form. Pair of intersecting lines

Find the value of angle ‘x’ in the figure. bar(AB)||bar(CD)

In the adjacent figure DeltaABC , bar(OB), bar(OC) are the angle bisectors of angleB, angleC respectively Intersect at 'O'. angleBOC =130^@ . If bar(OB)=bar(OC) , then find angleA, angleABC, angleACB .

In the given figure bar(PQ) is a line. Ray bar(OR) is perpendicular to line bar(PQ) . bar(OS) is another ray lying between rays bar(OP) and bar(OR) . Prove that angleROS = (1)/(2) angleQOS − anglePOS

ABC and DBC are two triangles where bar(AB) = bar(AC) and bar(DB) = bar(DC) . Show that /_ABC + /_DBC = /_ACB + /_DCB . Also S.T. AD is a bisector of /_A .

In figure, bar(AB) is a diameter of the circle, bar(CD) is a chord equal to the radius of the circle. bar(AC) and bar(BD) when extended intersect at a point E. Prove that angle AEB = 60^@ .

If the d.r's of bar(OA),bar(OB) are (1,-2,3),(-3,4,5) then the d.c's of the normal to the plane bar(OAB) are