Question

13. (a + 7) (a-10)+16​

Answer 1

Step-by-step explanation:

a²-10a+7a-70+16

a²-3a-54

Answer 2

(a + 7) (a - 10) + 16

_________ [ GIVEN ]

→ (a + 7) (a - 10) + 16

→ a(a - 10) (+7)(a - 10) + 16

→ a² - 10a + 7a - 70 + 16

→ a² - 3a - 54

Here a² - 3a - 54 is in the form ax² - bx - c.

We have to find factors of it such that it's product came 'c' and sum came 'b'

Here .. c = - 54 and b = - 3

» -9 and +6 are the numbers

Because sum of (-9) and (+6) is (-3) and product of (-9) and (+6) is (-54).

→ a² - 9a + 6a - 54

→ a(a - 9) +6(a - 9)

→ (a + 6) (a - 9)

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(a + 6) (a - 9) is the answer.

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