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.
 
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