Given that,
An equation : [tex]y=x^2+9x+20[/tex]
To find,
The zeros of the above function.
Solution,
To find zero, put y = 0
[tex]x^2+9x+20=0\\\\x^2+5x+4x+20=0\\\\x(x+5)+4(x+5)=0\\\\(x+4)=0\ \text{and}(x+5)=0\\\\x=-4\ \text{and}\ x=-5[/tex]
So, the zeros of the above quadratic equation is -4 and -5.