Answer:
Step-by-step explanation:
=7 (1+11+111+1111......n)
=7/9 (9+99+999+9999....n)
=7/9 ((10-1)+(10^2-1)+(10^3-1)+....n)
=7/9 ((10+10^2+10^3...n)-(1+1+1+1.....n))
=7/9 ((10 (10^n-1)/(10-1))-n)
The answer is: [C]: " 3 " .
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Explanation:
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4x - 1 = 2x + 5 ; Solve for "x" ;
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Subtract "2x" from each side of the equation; and add "1" to each side of the equation:
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4x - 1 - 2x + 1 = 2x + 5 - 2x + 1 ;
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2x = 6 ;
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Divide EACH side of the equation by "2" ; to isolate "x" on ONE side of the equation; and to solve for "x" ;
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2x / 2 = 6 / 2 ;
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x = 3 .
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The answer is: [C]: " 3 " .
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The correct answer is 63 i hope this helps out, have a nice day!!!
