SOLUTION: can you help me write this system as a matrix equation and solve using an inverse matrix please?... s + p + c = 40 c = 4p s = p

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Question 73125: can you help me write this system as a matrix equation and solve using an inverse matrix please?...
s + p + c = 40
c = 4p
s = p - 2
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
solve using an inverse matrix please?...
s + p + c = 40
c = 4p
s = p - 2
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Rearange equations #2 and #3 to get the variables in the same column:
s + p + c = 40
0 +4p - c = 0
1 - p + 0 =-2
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Enter the coefficient matrix into your calculator as matrix A:
1st Row: 1 ; 1; 1
2nd Row: 0 ; 4; -1
3rd Row: 1 ;-1; 0
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Enter the constants in as a 3x1 matrix called B:
1st Row: 40
2nd Row: 0
3rd Row: -2
--------------
Bring A to you home screen
Hit the "inverse" button
Hit the "multiply" button
Bring B to your home screen to the right of A^-1
Hit "enter"
You should see a 3x1 array with:
1st Row : 5 (this is s)
2nd Row : 7 (this is p)
3rd Row : 28 (this is c)
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Cheers,
Stan H.

SOLUTION: can you help me write this system as a matrix equation and solve using an inverse matrix please?... s + p + c = 40 c = 4p s = p - 2