Question

Х
a? +10a +21 a? -1
a²+6a-7
a +3​

Answer 1

Answer:

ANSWER

(a

2

+6a−7)

(a

2

+10a+21)

×

(a+3)

(a

−

1)

⇒

(a−1)+(a+7)

(a+3)(a+7)

×

(a+3)

(a−1)(a+1)

⇒1.