Evaluate these using identity :55 × 45

1.	Evaluate these using identity :55 × 45
Answer» 55 × 45 = (50 + 5) (50 – 5) Identity (a + b)(a – b) = a² – b² Here a = 50,b=5 (50 + 5)(50 – 5) = (50)² – 5² = 2500 – 25 55 × 45 = 2475

Answer»

55 × 45 = (50 + 5) (50 – 5)

Identity (a + b)(a – b) = a² – b²

Here a = 50,b=5

(50 + 5)(50 – 5) = (50)² – 5²

= 2500 – 25

55 × 45 = 2475

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