I have a few more questions.No problem, happy to help!

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Discussion Overview

The discussion revolves around finding the equation of a line that passes through the point (6, -3) with a given y-intercept of 8. Participants explore the process of determining the slope and using the point-slope formula to derive the line's equation.

Discussion Character

  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • Participants confirm that the y-intercept of 8 can be represented as the point (0, 8).
  • There is a discussion on finding the slope using the points (6, -3) and (0, 8), with some participants calculating the slope as m = -11/6.
  • One participant mentions using the point-slope formula to derive the equation of the line.
  • Another participant expresses that substituting (0, 8) into the equation y = mx + b confirms that b = 8, indicating the line crosses the y-axis at (0, 8).
  • Several participants derive the equation of the line as y = -11/6x + 8, confirming agreement on this result.

Areas of Agreement / Disagreement

Participants generally agree on the method to find the equation of the line and confirm the calculations leading to the same result. However, there is no explicit discussion of alternative methods or unresolved disagreements.

Contextual Notes

None noted.

Who May Find This Useful

Students learning about linear equations, particularly those seeking to understand the point-slope form and y-intercept in the context of line equations.

mathdad
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Find an equation of the line that passes through (6, -3) and has y-intercept 8.

The y-intercept 8 can be expressed as the point (0, 8).

Correct?

I then find the slope of (6, -3) and (0, 8).

Yes?

The next step is to plug one of the above points and the slope into the point-slope formula and solve for y.

Is any of this right?
 
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RTCNTC said:
Find an equation of the line that passes through (6, -3) and has y-intercept 8.

The y-intercept 8 can be expressed as the point (0, 8).

Correct?

Correct.

RTCNTC said:
I then find the slope of (6, -3) and (0, 8).

Yes?

Yes.

RTCNTC said:
The next step is to plug one of the above points and the slope into the point-slope formula and solve for y.

An equation for a line is y = mx + b where m is slope and b is the y-intercept. To write the equation of your line in this form we need the slope and y-intercept. For the y-intercept, what does the fact that (0, 8) is on the line tell you when you substitute for x and y in your y = mx + b equation?
 
greg1313 said:
Correct.
Yes.
An equation for a line is y = mx + b where m is slope and b is the y-intercept. To write the equation of your line in this form we need the slope and y-intercept. For the y-intercept, what does the fact that (0, 8) is on the line tell you when you substitute for x and y in your y = mx + b equation?

When I substitute (0,8) into y = mx + b, the answer is b = 8.
This means the graph crosses the y-axis at the point (0,8).
 
(6,-3) & (0,8)

m = (8-(-3))/(0-6)

m = (8+3)/(-6)

m = -11/6

I will use (0,8).

y - 8 = (-11/6)(x - 0)

y - 8 = (-11x/6)

y = (-11x/6) + 8

Yes?
 
We are given that the line has $y$-intercept 8, so your line may be written as:

$$y=mx+8$$

Now, we are given the point on the line $(6,-3)$, and so substituting for $x$ and $y$, we have:

$$-3=m(6)+8$$

Solving for $m$, we find:

$$m=-\frac{11}{6}$$

And so our line is:

$$y=-\frac{11}{6}x+8$$

This agrees with your result. (Yes)
 
MarkFL said:
We are given that the line has $y$-intercept 8, so your line may be written as:

$$y=mx+8$$

Now, we are given the point on the line $(6,-3)$, and so substituting for $x$ and $y$, we have:

$$-3=m(6)+8$$

Solving for $m$, we find:

$$m=-\frac{11}{6}$$

And so our line is:

$$y=-\frac{11}{6}x+8$$

This agrees with your result. (Yes)

Always good to know more than one method. BTW, thank you for answering my PM questions. I will reply in full later today...
 

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