SOLUTION: Trying to master slope intercept form, need to know how to solve for x intercept and y intercept in a problem similar to this : 8x + 7y = -5 what is the breakdown for solving for b

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Question 503726: Trying to master slope intercept form, need to know how to solve for x intercept and y intercept in a problem similar to this : 8x + 7y = -5 what is the breakdown for solving for both x and y intercepts?
Found 2 solutions by josmiceli, oberobic:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
You need to find
(x,0) ( the x-intercept ) and
(0,y) ( the y-intercept )
First, (x,0):
+8x+%2B+7y+=+-5+
+8x+%2B+7%2A0+=+-5+
+8x+=+-5+
+x+=+-%285%2F8%29+ is the x-intercept
and, (0,y):
+8%2A0+%2B+7y+=+-5+
+7y+=+-5+
+y+=+-%285%2F7%29+ is the y-intercept
--------------
Here's the plot:
+graph%28+400%2C+400%2C+-4%2C+4%2C+-4%2C+4%2C+-%288%2F7%29%2Ax+-+5%2F7%29+

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
y = mx+b is in slope-intercept form
b = y-intercept
m = slope
.
8x +7y = -5
7y = -8x -5
y = -8/7x - 5/7
.
m = -8/7 = slope
.
the y-intercept occurs where x=0
y = -8/7(0) -5/7
y = -5/7
y-intercept = (0,-5/7)
.
the x-intercept occurs where y=0
substitute and solve
0 = -8/7(x) -5/7
8/7x = -5/7
56 = -35x
x = -35/56
x = -7*5/7*8
x = -5/8
x-intercept = (-5/8,0)
.
graph%28500%2C500%2C-2%2C2%2C-2%2C2%2C-8%2F7%2Ax-5%2F7%29