-1

The expression $x^2-k^2$ where $k$ is a constant is equivalent to the expression $(x+a)(x-b)$ where $a$ and $b$ are constants. What is the value of $a-b$?

Michael Hardy
  • 1
Nicole
  • 1
  • Welcome to Math.SE! Questions are typically better received if you include some of your working or attempts on the problem - it allows people here to help you more effectively. – B. Mehta Apr 12 '18 at 01:53
  • 1
    Do you know how to factor a difference of squares? – Vasili Apr 12 '18 at 01:54
  • 4
    For $(x+a)(x-b)=x^2+(a-b)x-ab$ to be equivalent to $x^2-k^2=x^2+0x-k^2$, their coefficients must be the same. –  Apr 12 '18 at 01:54

1 Answers1

0

Hint

$$x^2 -k^2 = x^2 + 0x - k^2$$

Can you take this from here? Also take note of fourRightRotation's hint.

WaveX
  • 5,440