# Geometry

## Diagonal of parallelogram divide it into two congruent triangle

In this chapter we will prove important theorem of parallelogram. According to the theorem ” the diagonal of parallelogram divides the figure into two congruent triangle. “ Given above is parallelogram in which opposite sides are equal and parallel with AC as diagonal. To Prove:Prove that triangle ACD is congruent to triangle ACB. Proof:AB & …

## Questions on exterior angle of triangle

In this chapter we will discuss questions related to exterior angle theorem of triangle. All the questions are to the standard of grade 09. Question 01Observe the below image carefully and find value of all internal angle of triangle ABC. SolutionConsider the straight line EC.We know that in straight line, sum of all adjacent angle …

## Angle formed by angle bisector of triangle

In this chapter we will derive formula to calculate the value of angle formed by joining two angle bisector of triangle. Consider above triangle ABC in which BO & CO are angle bisectors dividing ∠B & ∠C into two equal parts. These angle bisectors meet at point O. The angle formed by angle bisector is …

## Questions on triangles & its angles

Given below are collection of questions related to triangle and its angles with detailed solution. All the questions are to the standard of grade 09. Question 01Given below is triangle ABC with ∠A = 55 and ∠B = 40 degree. Find the measure of ∠C. SolutionWe know that sum of all internal angle of triangle …

## Questions on parallel lines & transversal

Given below are collection of questions related to lines and angles. All questions are to the standard of grade 09. Question 01In the below image line AB is parallel to CD. Also ∠FED = 90 degree and ∠GED = 126 degree. Find the measure of angle ∠AGE, ∠GEF and ∠FGE. SolutionSince parallel lines AB & …

## Questions on lines & angles – set 02

Given below are collection of questions related to lined and angles. All the questions are provided with detailed solution. The questions are to the standard of grade 09. Question 01In the below image PQ & RS are two parallel lines. If ∠QXM = 135 degree and ∠RYM = 40 degree then find the measure of …

## Questions on lines & angles – set 01

Given below are collection of questions related to lines and angles. All questions are to the standard of grade 09 math. Question 01Consider the below figure in which ∠BOD = 40 degree and ∠ AOC + ∠ BOE = 70 degree. Find measure of ∠BOE & ∠COE. SolutionIt’s given that ∠BOD = 40 degree. Note …

## Adjacent angle on straight line measures 180 degree

In this chapter we will prove that sum of all adjacent angles in a straight lines measures 180 degree. AB is a straight line intersected by ray OM in between. The three angles formed in the above diagram are ∠AOM, ∠BOM & ∠AOB. We know that angle of straight line is 180 degree.∠AOB = 180 …

## Equal intercept theorem

In this chapter we will understand and prove the equal intercept theorem. Before moving on to learn the theorem, let us first understand the basics. What is an intercept ? When a transversal line intersect the two given lines then the length of transversal between the given two lines is called an intercept. For example, …

## Median of Right triangle property

The property states that ” in right triangle, the length of median that touches hypotenuse is half of the length of hypotenuse “. Consider the above right triangle ABC in which ∠ABC = 90 degree. Here BM is the median of triangle which divide the hypotenuse into two equal parts, AM = MC. According to …