MHB Finding the Equation of a Line Given Two Points

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To find the equation of the line passing through the points (6, -3) and with a y-intercept of 8, start with the slope-intercept formula y = mx + b, where b = 8. The y-intercept can be represented as the point (0, 8). The slope m is calculated using the formula m = (y2 - y1) / (x2 - x1), substituting the known values. After determining the slope, plug m and b into the slope-intercept equation to find the complete equation of the line. This method effectively utilizes both points and the y-intercept to derive the line's equation.
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Find an equation of the line that passes through (6, -3) and has y-intercept 8.

I know y = mx + b is the slope-intercept formula. In the formula, b represents the y-intercept. I also see that 8 is given to be b in this case.

The y-intercept can be written as (0, 8).

Do I now find the slope m?
Afterward, use one of the points and m to plug into the point-slope formula. Finally, I must isolate y.

Is this right?
 
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Like you, I would begin with the slope-intercept form of a line:

$$y=mx+b$$

We are given $b=8$, and we know two points on the line, so we can compute the slope $m$:

$$m=\frac{8-(-3)}{0-6}=$$?

Then, just plug in the values for $m$ and $b$. :)
 
MarkFL said:
Like you, I would begin with the slope-intercept form of a line:

$$y=mx+b$$

We are given $b=8$, and we know two points on the line, so we can compute the slope $m$:

$$m=\frac{8-(-3)}{0-6}=$$?

Then, just plug in the values for $m$ and $b$. :)

I can take it from here. Thanks.
 
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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