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## #1 2007-01-26 07:38:15

jxharmon
Member
Registered: 2007-01-08
Posts: 104

### Equation ?

How do I write an equation of the line with slope -2 and y-intercept (0,0)?

would it be
y=-2x or y= x -2

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## #2 2007-01-26 09:03:59

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Equation ?

The first one is correct. The slope determines the coefficient that goes before the x term and the y-intercept determines the constant term.

Basically, a line with slope a and y-intercept (0,b) will have the equation y = ax+b.

Why did the vector cross the road?
It wanted to be normal.

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## #3 2007-01-28 19:14:47

littlelittle
Member
Registered: 2007-01-24
Posts: 10

### Re: Equation ?

Hi

How did you solve this problem.  Can you explain it stepwise pl.

Thanks
S

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## #4 2016-12-25 14:35:22

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 700

### Re: Equation ?

littlelittle wrote:

Hi

How did you solve this problem.  Can you explain it stepwise pl.

Thanks
S

It's just as mathyperson said.
Since the line in question has slope -2 and y-intercept (0,0), so a = -2 and b = 0. Substitute them to the y = ax + b equation and you have:
y = ax + b
y = -2x + 0
y = -2x

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