Determine the slope

Question

Determine the slope of the line that is perpendicular to y=1/2x+3

 

Using the slope fro the above answer determine the equation of the line that is perpendiculare to y=1/2x+3 and passes through (4,5) and write the equation in slope -intercept form

Answer 1

So, Kim, the slope of a line parallel would be the same, or 1/2.  The slope of a perpendicular line is the opposite reciprocal.  Since the slope of our first line is 1/2, the slope of the 2nd is -2/1 = -2.

 

Now, we use our new slope with the x and y to find b, the y-intercept.  y = mx + b, right?  5 = -2(4) + b. 5 = -8 + b.  b = 13.

 

Now, we have our m and b.  y = -2x + 13 is your answer.

 

Hope this helps!