Answer:
Step-by-step explanation:
Basic quadratic equation has this following form:
[tex](x-x_{1})(x-x_{2})=0[/tex]
where x1 and x2 are the roots.
For [tex]x_{1}=1[/tex] and [tex]x_{2}=2[/tex], we can find:
[tex](x-1)(x-2)=0 \rightarrow x^{2}-2x-x+2=0 \rightarrow x^{2}-3x+2=0[/tex]