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Ex 12.2, 3 (vii) - Chapter 12 Class 7 Algebraic Expressions
Last updated at March 22, 2023 by Teachoo
Ex 12.2
Ex 12.2, 1 (i)
Ex 12.2, 1 (ii) Important
Ex 12.2, 1 (iii)
Ex 12.2, 1 (iv) Important
Ex 12.2, 1 (v) Important
Ex 12.2, 1 (vi)
Ex 12.2, 2 (i)
Ex 12.2, 2 (ii) Important
Ex 12.2, 2 (iii)
Ex 12.2, 2 (iv)
Ex 12.2, 2 (v) Important
Ex 12.2, 2 (vi)
Ex 12.2, 2 (vii) Important
Ex 12.2, 2 (viii) Important
Ex 12.2, 2 (ix)
Ex 12.2, 2 (x) Important
Ex 12.2, 3 (i)
Ex 12.2, 3 (ii) Important
Ex 12.2, 3 (iii)
Ex 12.2, 3 (iv)
Ex 12.2, 3 (v) Important
Ex 12.2, 3 (vi)
Ex 12.2, 3 (vii) Important You are here
Ex 12.2, 3 (viii) Important
Ex 12.2, 4 (a)
Ex 12.2, 4 (b) Important
Ex 12.2, 5
Ex 12.2, 6 (a)
Ex 12.2, 6 (b) Important
Transcript
Ex 12.2, 3 (Method 1) Subtract: (vii) 5a2 – 7ab + 5b2 from 3ab – 2a2 – 2b2 (3ab – 2a2 – 2b2) − (5a2 – 7ab + 5b2 ) = 3ab – 2a2 – 2b2 − 5a2 + 7ab − 5b2 = −2a2 − 5a2 − 2b2 − 5b2 + 3ab + 7ab = a2 (−2 − 5) + b2 (−2 − 5) + ab (3 + 7) = a2 (−7) + b2 (−7) + ab (10) = −7a2 − 7b2 + 10ab Ex 12.2, 3 (Method 2) Subtract: (vii) 5a2 – 7ab + 5b2 from 3ab – 2a2 – 2b2 We need to subtract ((5a2 – 7ab + 5b2 ) from (3ab – 2a2 – 2b2) 5a2 − 7ab + 5b2 from 3ab − 2a2 − 2b2 Answer is 10ab – 7a2 – 7b2
