SOLUTION: Solve this problem using the substitution method 4x - y = -3 y - 3 = 4x

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Question 74366: Solve this problem using the substitution method
4x - y = -3
y - 3 = 4x
Found 3 solutions by stanbon, checkley75, jim_thompson5910:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve this problem using the substitution method
4x - y = -3
y - 3 = 4x
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Solve the 2nd equation for y: y=4x+3
Substitute that into the 1st equation to solve for "x":
4x-(4x+3)=-3
4x-4x-3=-3
-3=-3
This means the two equations are dependent which means one
is a multiple of the other. It also means that every point
on the line y=4x+3 is a solution for the system of equations.
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Cheers,
Stan H.

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
Y-3=4X, Y=4X+3 NOW SUBSTITUTE (4X+3) FOR Y IN THE OTHER EQUATION & SOLVE FOR X
4X-(4X+3)=-3
4X-4X+12=-3
0=-3-12
0=-15 NO SOLUTION.
THESE ARE THE SAME EQUATION IN DIFFERENT FORMS WITH 2 UNKNOWNS. THUS NO SLUTION.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
4x+-+y+=+-3
y+-+3+=+4x
y+=+4x%2B3Solve the 2nd equation for y. Plug this into the 1st equation
4x+-+%284x%2B3%29+=+-3
cross%284x+-+4x%29-3+=+-3
-3=-3
This answer shows us that any x will give us a solution. For instance let x=1
y+-+3+=+4%281%29
y+=+4%2B3
y+=+7


Check:
4%281%29+-+7+=+-3Plug in (1,7)
7+-+3+=+4%281%29
-3+=+-3Works
4+=+4Works
So (1,7) is a solution. If we pick any number for x, we can get y. So our solution set is (x,4x+3). This means there are an infinite number of solutions. This is simply because the equations are the same line (try to solve for y for each of them).