In Fig. 6.57, state the three pairs of equal parts in ∆ABC and ∆EOD. Is ∆ABC ≅ ∆ EOD? Why? Fig. 6.57 1. Draw an equilateral triangle of side 6 cm, an isosceles triangle of base 3 cm and equal sides 6 cm each and a scalene triangle of sides 3 cm, 6 cm and 7 cm. Now draw a median and an altitude in each triangle from the top vertex, measure and tabulate the lengths of all the medians and altitude’s of respective triangles. What can you conclude from this activity (This activity can also be done by paper folding)? 2. Draw two triangles which have a pair of corresponding sides equal but are not congruent. 3. Draw two triangles which have two pairs of corresponding sides equal but are not congruent. 15-04-2018 4. Draw two triangles, which have one pair of corresponding angles equal and one pair of corresponding sides equal but are not congruent. 5. Draw two triangles which have three pairs of corresponding angles equal but are not congruent. Solve the given cross number/word and then fill up the given boxes in activities 6 and 7. Clues are given below for across as well as downward fillings. For across and downward clue numbers are written at the corner of boxes. Answers of clues have to fill up in their respective boxes. Cross Number Puzzle 6 Across
This question refers to a figure in the original PDF.
- (a)If 6, 8, m are the sides of a right triangle, then the value of m is ______.
- (b)In ∆ABC, AC is the longest side, then what can be the measure of angle B (in degree), if the three angles of triangle are 120°, 40°, 20°?
- (c)In a right-angled triangle, one acute angle measures twice the other angle, then the smaller angle shall measure _________.
- (d)If three angles in ∆ABC are in the ratio 2 : 3 : 5, then measure of ∠B is _____. (e) Length of third side of a triangle whose two sides are 5 cm and 6 cm, must be less than _______. (f) The perimeter of ∆ABC in Fig. 6.58 is _________. Fig. 6.58 15-04-2018 Down (a) In an isosceles triangle if one of the equal angles measures 35°, then the third angle is __________. (b) In Fig. 6.59, the value of x is _________. Fig. 6.59 (c) The sum of the angles in a quadrilateral is ___________. (d) In ∆ ABC, ∠B = 80°, ∠ A = 30°, the bisectors of ∠B and ∠C meet at O. The measure of ∠BOC is ___________. 15-04-2018 Cross Word Puzzle 7 Across 1. A triangle with all its sides unequal. 2. The longest side of a right-angled triangle. 3. Two squares having same side lengths. 4. Line segment drawn from a vertex of a triangle perpendicular to its opposite side. Down 5. A type of triangle in which altitude falls outside the triangle. 6. A line segment joining vertex with the mid-point of the opposite side. 7. A regular triangle. 8. In a parallelogram, the line segment that divides it into two congruent triangles. 15-04-2018