Find the measure of the acute angle between the lines represented by `x^(2) + 4xy + y^(2) = 0`.

The acute angle between the lines represented by x^(2) + xy = 0 is….

The acute angle between the lines represented by 6x^(2)-xy-y^(2)=0 is

The acute angle between the lines represented by 6x^(2)-xy-y^(2)=0 is

Acute angle between the lines represented by 3x^(2)-48xy+23y^(2)=0 is

Acute angle between the lines represented by 3x^(2)-48xy+23y^(2)=0 is

Find the measure of the acute angle between the lines represented by (a^(2) - 3b^(2)) x^(2) + 8abxy + (b^(2) - 3a^(2)) y^(2) = 0.