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

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To find the equation of the line passing through the point (6, -3) with a y-intercept of 8, the y-intercept can be represented as the point (0, 8). The slope is calculated using the formula m = (y2 - y1) / (x2 - x1), resulting in m = -11/6. Substituting this slope and the y-intercept into the point-slope formula yields the equation y = -11/6x + 8. This confirms the line's equation is y = -11/6x + 8, aligning with the initial conditions provided.
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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...
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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