The associative property of addition is pretty much just any numbers in place of these: a + (b + c) = (a + b) + c. Therefore, your answer would be d) (6 + 1) + 9 = 6 + (1 + 9)


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- BCD is an isosceles right triangle , right angled at D
- ABC is an equilateral triangle


❒ Sum of all angles is 180° , since it is an equilateral triangle all the three angles would be same





(Isosceles triangle)









Increases proportionally. (C)