On the first question, the formula would be m=\frac{y2-y1}{x2-x1} and the value we got is -4/3, so D. On the second quesiton, the slope in the given equation of the line is -2, its negative reciprocal is 1/2, so A. On the third question, use the slope formula above and the value you would get is zero, so A. On the fourth question, the equation of the line perpendicular to line QR is y=2x+b, to find b, just substitute the point (5,6) to the equation. That would make b = -4. the final equation of the line would be: y=2x-4, so D. On the fifth question, the equation of the line parallel to line QR is y = -2x + b. substitute the point (4,5) to the equation, and you'll get b = 13. the final equation of the line would be y=-2x+13, so A.
