Use Cramer's Rule to Solve the System of Equations $\{ ( 5 , - 1 ) \}$

Multiple Choice

Use Cramer's rule to solve the system of equations. If D = 0, use another method to determine the solution set.
x+y=4
5x +5y =20

A) $\{ ( 5 , - 1 ) \}$
B) Cramer's rule does not apply since $D = 0 ; \phi$
C) $\{ ( 0,0 ) \}$
D) Cramer's rule does not apply since $\mathrm { D } = 0 ; \{ ( 4 - \mathrm { y } , \mathrm { y } ) \}$