Use an equation to find the value of k so that the line that passes through ( k , 6 ) and ( 1 , 3 ) has a slope of m = − 1 .

Answer 1

Slope intercept form is y=mx+b. M= -1, which means your slope is -1. So far the equation is y=-x+b. Now you need to find b which is the y-intercept. To find b, you will use the point (1,3). You will plug it in into the equation, it will look like this 3=-1(1)+b. Now you solve for b. Multiply -1 and 1 you get -1. Add 1 to both sides and you have b=4. So the equation is y=-x+4. So to find k, plug in the point (k,6). It will look like this 6=-k+4. Subtract 4 on both sides. 2=-k is what you have so far. Divide by -1 on both sides. THE ANSWER IS K=-2.