Question

X square + 10 X + 21​

Answer 1

x^2+10x+21

x^2+7x+3x+21

x(x+7)+3(x+7)

(x+7)(x+3)

x=-7 ., x=-3

hope it helps you .

Answer 2

Answer:

Factorisation method.

Step-by-step explanation:

x^2 + 10x + 21

x^2 + 7x + 3x + 21

x(x+7) + 3(x+7)

(x+3)=0 or (x+7)=0

Therefore,

x=-3, x=-7.

Hope it helps.

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