Question

1. Use suitable identities to find the following products:
(i) (x + 4) (x+10)

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Answer 1

Identity:

An identity is an equality which is true for all values of a variable in the equality.

eg:-(x + a) (x + b) = x²+(a + b) x + ab

In an identity the right hand side expression is called expanded form of the left hand side expression.

Solution:

Using identity,

[(x + a) (x + b) = x² + (a + b) x + ab]

In (x + 4) (x + 10),

a = 4 & b = 10

Now,

(x + 4) (x + 10)

= x² + (4 + 10)x + (4 × 10)

= x²+40x + 40

Answer 2

Step-by-step explanation:

(x+4) (x+10)

(x +a) (x+b)=x^2+(a+b)x+ab

a=4

b=10

=>x^2+(4+10)x+4(10)

=x^2+14x+40