question_answer

\[{{a}_{1}}x+{{b}_{1}}y+{{c}_{1}}=0\] and \[{{a}_{2}}x+{{b}_{2}}y+{{c}_{2}}=0,\]where \[{{a}_{1}},{{b}_{1}},{{c}_{1}},{{a}_{2}},{{b}_{2}},{{c}_{2}}\] are all real numbers and \[a_{1}^{2}+b_{1}^{2}\ne 0,\] \[a_{2}^{2}+b_{2}^{2}\ne 0,\] is called a:

A) family of two different straight lines

B) family of two coincident lines

C) pair of linear equations in two variables

D) None of the above