SOLUTION: How would you find the equation of a line if you were given the slope and the x-intercept? This is a challenge question for our class for discussion. I am not sure how to answer

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Question 66145This question is from textbook Beginning Algebra
: How would you find the equation of a line if you were given the slope and the x-intercept?
This is a challenge question for our class for discussion. I am not sure how to answer this because I have dealt with the y-intercepts but not the x-intercepts. Could you give me an description on how to find the equation of a line. Thanks. This question is from textbook Beginning Algebra

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
y+=+mx+%2B+b is the slope-intercept form of a straight line
The y-intercept occurs when x=0
The x=intercept occurs when y=0
You say that the slope is known and the x-intercept is known
m is the slope, so lets say (m+=+m%5B1%5D)
The x-intercept is at (x%5B1%5D%2C+0)
y+=+mx+%2B+b
When y=0,
0+=+m%5B1%5Dx%5B1%5D+%2B+b
b+=+-m%5B1%5Dx%5B1%5D
So, the equation of the line becomes
y+=+m%5B1%5Dx+-+m%5B1%5Dx%5B1%5D
Let's try an example
m[1] = -1
x[1] = 7
y+=+m%5B1%5Dx+-+m%5B1%5Dx%5B1%5D
y+=+-x+-+%28-1%29%2A7
y+=+-x+%2B+7
When y=0, x=7 as it should
When x =0 y = 7 also