Question

in the polynomial below what number should replace the question mark to produce a difference of squares? x^2+?x-25
A.0
B.25
C.5
D.10

Answer 1

Hello from MrBillDoesMath!

Answer:   A

Discussion:

An unusual question. Note that if   "? = 0" then

x^2 + ?x - 25 = x^2 + 0 - 25 = x^2 - 25 = (x+5)(x-5)

Thank you,

MrB

Answer 2

Answer:

? = 0

A is correct.

Step-by-step explanation:

Given: Polynomial $x^2+?x-25$

We need to make it difference of square.

It is quadratic form.

$y=ax^2+bx+c$

Difference of square:

$y=x^2-d^2$

For difference of square the x term can't be there.

Thus, The coefficient of x must be 0 for quadratic equation.

$ax^2+bx+c\rightarrow x^2-d^2$

coefficient of x must be 0

$x^2+?x-25\rightarrow x^2+0x-25$

$?\rightarrow 0$

Hence, The question marks replace by 0 to make equation perfect square.