Answer:
[tex] {y}^{2} - 9 = 0[/tex]
Step-by-step explanation:
as both 3 and - 3 are possible values of y;
[tex]y = 3 \: or \: y = - 3[/tex]
[tex]y - 3 = 0 \: or \: y + 3 = 0[/tex]
therefore;
[tex](y - 3)(y + 3) = 0[/tex]
by expanding;
[tex] {y}^{2} - {3}^{2} = 0[/tex]
[tex] {y }^{2} - 9 = 0[/tex]
