Question

what number should be subtracted from x^2 + 8 x + 20 get (X + 4)^2​

Answer 1

Question :----

• we have to find what number whould be subtracted from x² + 8x +20 to get (x+4)² ?

Formula used :----

• (a+b)² = a² + b² + 2ab

Solution :-----

First lets solve (x+4)² by above formula , we get,

(x+4)² = x² + 16 + 8x

Now,

To Find the required number ,

subtraction x² + 16 + 8x from x² + 8 x + 20 ..

so, we get,

(x² + 8x +20) - (x² + 8x +16)

→ x² + 8x + 20 - x² - 8x -16

→ x² - x² + 8x - 8x + 20 - 16

→ 20 - 16

→ 4 (Ans)

Hence, if we subtract 4 from x² + 8 x + 20 we will get , (x+4)² ....

(Hope it helps you)