SOLUTION: Prove that given: {{{matrix(1,3,(5x-1)/8,""="",3)}}} then {{{x=5}}}

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Question 1150961: Prove that given:
matrix%281%2C3%2C%285x-1%29%2F8%2C%22%22=%22%22%2C3%29
then
x=5
Found 2 solutions by Edwin McCravy, MathLover1:
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
matrix%281%2C3%2C%285x-1%29%2F8%2C%22%22=%22%22%2C3%29

Multiply both sides by 8:

matrix%281%2C3%2C8%2A%28%285x-1%29%2F8%29%2C%22%22=%22%22%2C8%2A%283%29%29

matrix%281%2C3%2Ccross%288%29%2A%28%285x-1%29%2Fcross%288%29%29%2C%22%22=%22%22%2C24%29

matrix%281%2C3%2C5x-1%2C%22%22=%22%22%2C24%29

Add +1 to both sides:

matrix%281%2C3%2C5x-1%2B1%2C%22%22=%22%22%2C24%2B1%29

matrix%281%2C3%2C5x-cross%281%29%2Bcross%281%29%2C%22%22=%22%22%2C24%2B1%29

matrix%281%2C3%2C5x%2C%22%22=%22%22%2C25%29

Divide both sides by 5:

matrix%281%2C3%2C%285x%29%2F5%2C%22%22=%22%22%2C25%2F5%29

matrix%281%2C3%2C%28cross%285%29x%29%2Fcross%285%29%2C%22%22=%22%22%2C5%29

matrix%281%2C3%2Cx%2C%22%22=%22%22%2C5%29

Proved

Edwin

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Statements..................... Reasons
1. %285x-1%29%2F8=3..................... Given
2. 5x-1=24..................... both sides of (1) multiply by 8
3. 5x-1%2B1=24%2B1..................... Addition of 1 to equation (2)
4. 5x%2B0=24%2B1..................... Substitution of -1+%2B+1+=+0 into (3)
5. 5x=25..................... Substitution of 5x+%2B+0+=+5x and 24+1=25 into (4)
6. 5x=25 ..................... Dividing equation (5) by 5
7. x=5.....................Substitution of 25%2F5+=+5 into (6)