Answer:
não sei não falo seu idioma
We need to FOIL that out and then get it into standard form to see what our A, B, and C are. FOILing gives us

. If we move the 7 over by subtraction and set it equal to 0, we have

. In order to avoid a negative leading coefficient, we can change all the signs to get

so A = 1, B = 0, C = -18, first choice above.
Hello!
A rhombus is any quadrilateral that has congruent side lengths. A square has all four sides the same length, so a square can be considered a rhombus.
I hope this helps!
X - y + 6 = 0
slope - intercept form is
y = x + 6