SOLUTION: graph the line y-4= -2(x+1) Please help I don't know where to begin

Algebra ->  Graphs -> SOLUTION: graph the line y-4= -2(x+1) Please help I don't know where to begin      Log On


   

Question 215993: graph the line y-4= -2(x+1) Please help I don't know where to begin
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Graph the line y-4= -2(x+1) Please help I don't know where to begin.

Step 1. Put the equation in slope-intercept form given as y=mx+b where m is the slope and b is the y-intercept at point (0,b) or x=0 and y=b.

y-4=-2%28x%2B1%29

Step 2. Add 4 to both sides of the equation to get the equation in slope-intercept form.

y-4%2B4=-2%28x%2B1%29%2B4

y=-2x-2%2B4

y=-2x%2B2

Note the slope m=-2 and the y-intercept b=2. (see graph on last step)

Step 3. Now, it takes two points to draw a line. Say we pick one point is at x=0 then evaluate y and the other point is y=0 and find x. These points are relatively easy to find when compared to other points on the line.

Step 4. Find y when x=0

y=-2x%2B2=-2%2A0%2B2=2

So at x=0, then y=2 or we have point (0,2) as one point.

Step 5. Find x when y=0

0=-2x%2B2

Add 2x to both sides of the equation.

0%2B2x=-2x%2B2%2B2x

2x=2

Divide 2 to both sides of the equation to get x

2x%2F2=2%2F2

x=1

Now we have the other point at (1,0)

Step 6. Use the two points (0,2) and (1,0), to plot the graph below

graph%28+600%2C+600%2C+-5%2C+5%2C+-5%2C+5%2C+-2x%2B2%29+

Note the slope m=-2 and the y-intercept b=2=y at x=0 and it passes through the points (0,2) and (1,0).

I hope the above steps were helpful.

For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

Good luck in your studies!

Respectfully,
Dr J