When solving an equation using desmos, how many solutions do you have when a single vertical line crosses the x-axis?

Only 1 solution because you pass through the x-axis only once. Here is an example image below.

Answer to your question: a. the fundamental theorem of algebra tells you that the equation will have two complex roots since the degree of the polynomial is 2. the roots are ​ x=1±i7√2 .number of roots=degree of polynomialhere, degree of polynomial is 2 so number of roots will be 2.hope it *_*