She should multiply both sides of the equation by (y - 1)(y + 1)
The equation is given as:
y+y^2-5/y^2-1=y^2+y+2/y+1
Rewrite properly as:
[tex]\frac{y+y^2-5}{y^2-1}=\frac{y^2+y+2}{y+1}[/tex]
Express the denominator as a difference of two squares
[tex]\frac{y+y^2-5}{(y - 1)(y +1)}=\frac{y^2+y+2}{y+1}[/tex]
Next, multiply both sides of the equation by (y - 1)(y + 1)
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