SOLUTION: solve 3 to the power x *3 to the power-y= 9 and 2 power y *4 power -x=1/8 please help me

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Question 651696: solve 3 to the power x *3 to the power-y= 9 and 2 power y *4 power -x=1/8
please help me
Answer by MathTherapy(10552) About Me  (Show Source):
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solve 3 to the power x *3 to the power-y= 9 and 2 power y *4 power -x=1/8
please help me

3%5Ex+%2A+%283%5E%28-+y%29%29+=+9
3%5E%28x+%2B+%28-+y%29%29+=+9
3%5E%28x+-+y%29+=+9
3%5E%28x+-+y%29+=+3%5E2

Since bases are equal, then x – y = 2 ---- eq (i)

2%5Ey+%2A+%284%5E%28-+x%29%29+=+1%2F8
2%5Ey+%2A+%282%5E2%29%5E%28-+x%29+=+1%2F8
2%5Ey+%2A+%282%5E%282+%2A+%28-+x%29%29%29+=+1%2F8
2%5Ey+%2A+%282%5E%28-+2x%29%29+=+1%2F8
2%5E%28y+%2B+%28-+2x%29%29+=+1%2F8
2%5E%28y+-+2x%29+=+1%2F8
2%5E%28y+-+2x%29+=+2%5E-3

Since bases are equal, then: y - 2x = - 3 ---- - 2x + y = - 3 ----- eq (ii)

x – y = 2 ---- eq (i)
- 2x + y = - 3 ----- eq (ii)
- x = - 1 ----- Adding eqs (ii) & (i)

highlight_green%28x+=+1+%29

1 – y = 2 -------- Substituting 1 for x in eq (i)
- y = 2 - 1
- y = 1

highlight_green%28y+=+-+1%29

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