Q1 of 86 Page 56

Use suitable identities to find the following products

(x + 5) (x + 2)

using the identity (x + a) × (x + b) = x2 + (a + b)x + ab


here a = 5 and b = 2


⇒ (x + 5) (x + 2) = x2 + (5 + 2)x + 5 × 2


Therefore (x + 5) (x + 2) = x2 + 7x + 10


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