Find the slope, if it exists: 2x+4y=7 Solution A straight line always has a slope. The slope is merely the change in the value of y for a change in the value of x. The equation of the line given is 2x + 4y = 7 2x + 4y = 7 => 4y = 7 - 2x => y = (7/4) - (x/2) This is in the form y = mx + c where m is the slope. Here m = -1/2 The slope of the given line is -1/2.