Question

Fan and medal.
X^2-9=0
A. X=+3
B. X=+9
C. X=0
D. No solution
Can u show the steps on how to do it?

Answer 1

Do you know how to rearrange equations?

Answer 2

hint: \(\textit{difference of squares}
\\ \quad \\
(a-b)(a+b) = a^2-b^2\qquad \qquad
a^2-b^2 = (a-b)(a+b)\)

Answer 3

\(\bf x^2-9=0\qquad {\color{brown}{ 9=3^2}}\implies x^2-{\color{brown}{ 3^2}}=0\)

Answer 4

i know all that but im wondering if the answer is 3 or 0

Answer 5

X^2-9=0

(x + 3) * (x - 3) = 0

x + 3 = 0 OR x - 3 = 0

x = - 3 or x = + 3

@Casadie1004

Answer 6

Lol, if we're just giving answers away then:
\[x^2-9=0\]
\[x^2-9+9=0+9\]
\[x^2=9\]
\[\sqrt{x^2}=\sqrt{9}\]
\[x=\pm3\]