Y= 4x +3, 4x + y =3 are they parallel or perpendicular

they are perpendicular  

Step-by-step explanation:

because the slope are opposite which means the lines intersect.

Neither

Step-by-step explanation:

When two lines are parallel, their slopes are the same.

When two lines are perpendicular, their slopes are opposite reciprocals. Opposite reciprocals equal -1 when multiplied together.

Equation #1: y = 4x + 3

The equation is in the form y = mx + b, so the slope is 4.

Equation #2: 4x + y = 3

We need to put this equation in slope-intercept form.

1) Subtract 4x from both sides

y = -4x + 3

The slope is -4.

-4 and 4 are neither equal nor opposite reciprocals, so they aren't parallel or perpendicular.