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How would you sketch a plot of the line on y=-2x+16

User MeBigFatGuy
by
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1 Answer

23 votes
23 votes

Answer: Draw a straight line through (0, 16) and (1, 14)

The graph is below.

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Step-by-step explanation:

There are at least two approaches we can take

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Method 1

Plug in x = 0 to find that....

y = -2x+16

y = -2(0)+16

y = 16

The point (x,y) = (0,16) is on the line. This is the y intercept

Repeat similar steps for x = 1

y = -2x+16

y = -2(1)+16

y = 14

The point (1, 14) is also on the line

Plot the points (0, 16) and (1, 14). Then draw a straight line through them to complete the graph for y = -2x+16

You only need 2 points at minimum to draw a linear graph.

The graph is shown below. Ignore the stuff in red.

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Method 2

Compare y = -2x+16 to the form y = mx+b

  • m = -2 = slope
  • b = 16 = y intercept

The y intercept is where the graph crosses the y axis. In this case, it's at the location (0, 16)

Start at this point and move down 2 units and to the right 1 unit to arrive at (1, 14) which is another point on the line.

The stuff in red shows this motion of "down 2, right 1"

note that slope = -2 = -2/1 = rise/run

rise/run = -2/1

rise = -2 = go down 2

run = 1 = go to the right 1

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Side note: You can use a graphing tool like Desmos or GeoGebra to graph quickly. I used GeoGebra to make the diagram below. Though it's handy to have practice to do it by hand.

How would you sketch a plot of the line on y=-2x+16-example-1
User Dfperry
by
3.2k points