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Give the slope and y-intercept for the equation: y=3x-2

Y=3x-2

y intercept means where x=0

put x=0 in the equation

y=3(0)-2

Y=-2

if we start with this general form:

Ax + By + C=0

Then the slope of the line is:

slope = m = -A/B

And the y-intercept is:

y-intercept = b = -C/B

so in this equation y=3x-2

c=-2

b=1

slope=2/1

slope=2

Hope that will help you....

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You're correct, up to this point.y=3x-2

y intercept means where x=0

put x=0 in the equation

y=3(0)-2

y=-2

if we start with this general form:

Ax + By + C=0

Then the slope of the line is:

slope = m = -A/B

And the y-intercept is:

y-intercept = b = -C/B

(I changed symbols Y above to y; it's best to use just one symbol.)

Remember, A=-3, B=1, C=2so in this equation y=3x-2

c=-2 C=2; it becomes -2 on the right, after subtracting it from each side.

b=1 That ought to say B=1. You're mixing up your symbols B (coefficient) and b (y-intercept)

-C/B = -2/1 so b = -2

slope=2/1 2 is not the correct value in -A/B

slope=2

-3x + y + 2 = 0 :cool:

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Hi. It's easy to answer, if you've learned this special form:Give the slope and y-intercept for the equation: y=3x-2

Slope-Intercept Form

Have you seen it? Google "slope intercept form", or look it up in your textbook's index. You'll learn that the equation y=3x-2 is written in Slope-Intercept Form because the two numbers shown are the slope and the y-intercept.

If you're not sure what "slope" or "y-intercept" mean, then you ought to learn those names first.

Let us know, if you have any questions about what you read in your textbook or see in online lessons. :cool:

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http://www.virtualnerd.com/algebra-1/linear-equation-analysis/slope-intercept-form/slope-intercept-form-examples/slope-intercept-form-definition

Im confused, i thought in slope intercept form the 3x would be the slope. But you're saying its 2?Y=3x-2

y intercept means where x=0

put x=0 in the equation

y=3(0)-2

Y=-2

if we start with this general form:

Ax + By + C=0

Then the slope of the line is:

slope = m = -A/B

And the y-intercept is:

y-intercept = b = -C/B

so in this equation y=3x-2

c=-2

b=1

slope=2/1

slope=2

Hope that will help you....

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y=mx +b is in slope intercept form where slope = m and y-int=b.Im confused, i thought in slope intercept form the 3x would be the slope. But you're saying its 2?

You are correct (almost). Slope =3 in your question (not 3x just 3).

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Im confused, i thought in slope intercept form the 3x would be the slope. But you're saying its 2?

Hi Bronn,

first of all sorry i solved it wrong as i just put those values in y intercept equation,

Ax+By+C=0

Y=3X-2

3X-Y-2=0

m(slope)=-A/B

A=3,B=-1

here A=-(-3)/1

slope=3

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see comment in redGive the slope and y-intercept for the equation: y=3x-2

y=mx + c

m=slope

Therefore slope = 3

y-intercept is where it cuts the x- axis (when y=0) ...ummm NO! It is called the y-intercept because that is where it cuts the y-axis not the x-axis!!

Therefore 0=3x-2 ===> 2=3x ===> 2/3=x when y=0 i.e. (2/3,0) is the point at which it cuts the x-axis

I may aswell ask here. Ive just been learning this stuff. Ive been confused what the C represents. I get that M is slope, the ab and xy are coordinates right? but what does the C represent?Hi Bronn,

first of all sorry i solved it wrong as i just put those values in y intercept equation,

Ax+By+C=0

Y=3X-2

3X-Y-2=0

m(slope)=-A/B

A=3,B=-1

here A=-(-3)/1

slope=3

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- 1,103

Hi Bronn,I may aswell ask here. Ive just been learning this stuff. Ive been confused what the C represents. I get that M is slope, the ab and xy are coordinates right? but what does the C represent?

There are basically two forms of the equation of a straight line.

1. Gradient intercept form: \(\displaystyle y = mx+c \). This form always starts with \(\displaystyle y=\). The gradient is m (the coefficient of x) and the y-intercept is c (constant term).

In this form it is easy to just pick out the gradient and y-intercept. Hence the name.

2. Standard form: \(\displaystyle Ax + By +C = 0\)

This form can be rearranged into gradient-intercept form in the following way:

\(\displaystyle Ax + By + C =0\)

\(\displaystyle By= -Ax - C\)

\(\displaystyle y=\frac{-A}{B}x - \frac{C}{B}\)

So the gradient (the coefficient of x) = \(\displaystyle \frac{-A}{B}\) and the y-intercept is \(\displaystyle \frac{-C}{B}\).

Note that the c's mean different things. That's why one is usually lower case and one upper case.

(x, y) represents points on the line and are thethe ab and xy are coordinates right?

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so the A and B are constants in standard form, not the same as the (a,b) in point slope form? i.e. (y-b) = m(x-a)Hi Bronn,

There are basically two forms of the equation of a straight line.

1. Gradient intercept form: \(\displaystyle y = mx+c \). This form always starts with \(\displaystyle y=\). The gradient is m (the coefficient of x) and the y-intercept is c (constant term).

In this form it is easy to just pick out the gradient and y-intercept. Hence the name.

2. Standard form: \(\displaystyle Ax + By +C = 0\)

This form can be rearranged into gradient-intercept form in the following way:

\(\displaystyle Ax + By + C =0\)

\(\displaystyle By= -Ax - C\)

\(\displaystyle y=\frac{-A}{B}x - \frac{C}{B}\)

So the gradient (the coefficient of x) = \(\displaystyle \frac{-A}{B}\) and the y-intercept is \(\displaystyle \frac{-C}{B}\).

Note that the c's mean different things. That's why one is usually lower case and one upper case.

(x, y) represents points on the line and are thevariables. A and B and C OR m and c areconstantsfor a particular line.

this could get confusing for me..

edit: after clicking the point slope link above, i see maybe using (a,b) in point slope form is a kahn academy thing

Last edited: