The graphs of the lines $x+2y-3=0$ and $2x+4y+11=0$ are

Compare the given system of lines to the standard equations $a_{1}x+b_{1}y+c_1=0$ and $a_{2}x+b_{2}y+c_2=0$:Line 1: $1x+2y-3=0⟹a_1=1,b_1=2,c_1=-3$ Line 2: $2x+4y+11=0⟹a_2=2,b_2=4,c_2=11$ Check the ratios of the coefficients:
$$\frac{a_1}{a_2}=\frac{1}{2}$$
$$\frac{b_1}{b_2}=\frac{2}{4}=\frac{1}{2}$$
$$\frac{c_1}{c_2}=\frac{-3}{11}$$
Since $\frac{a_1}{a_2}=\frac{b_1}{b_2}\ne \frac{c_1}{c_2}$, the lines have no solution and are strictly parallel to one another.