How do you graph $y=-6+2x$ using the intercepts?

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Answer 1 · 2016-06-07T16:05:27

$color(blue)(=>y_("intercept") ->(x,y) = (0,-6))$

$color(blue)(=>x_("intercept") ->(x,y) = (3,0))$

Find the points of intercepts and draw a line through them.

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)("Determine the "x" intercept")$

The line crosses the x-axis at $y=0$ so by substitution we have:

$color(brown)(y=2x-6)color(green)(" "->" "0=2x-6)$

Add 6 to both side so that the 6 on the right becomes 0

$6=2x+0$

Divide both sides by 2 so that the 2 from $2x$ becomes 1. This is because $1xx x=x$ . That is, you get rid of the 2 on the right.

$6/2=2/2xx x$

$3=x$

$color(blue)(=>x_("intercept") ->(x,y) = (3,0))$

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)("Determine the "y" intercept")$

The line crosses the y-axis at $x=0$ so by substitution we have:

$color(brown)(y=2x-6)color(green)(" "->" "y=2(0)-6)$

But $2xx0=0$

$y=0-6$

$y=-6$

$color(blue)(=>y_("intercept") ->(x,y) = (0,-6))$
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Tony B

How do you graph y=-6+2xy=-6+2x using the intercepts?