The mistake is in the third step, the subtraction was done without taking LCM. The value of x is -36.
What is simplification?
The numerical expression having two or more operations can be simplified by using ‘BODMAS’ rule, where the letters B, O, D, M, A, S stand for Brackets , orders (powers/indices or roots) , Division, Multiplication, Addition and Subtraction respectively.
For the given situation,
The expression is 1/3 (1/2x -9) = 1/2 ( x + 18).
We need to simplify the expression to find the mistake done by them.
⇒ [tex]\frac{1}{3}(\frac{1}{2}x-9 ) = \frac{1}{2}(x+18)[/tex]
⇒ [tex]\frac{1}{6}x-3 = \frac{1}{2}x+9[/tex]
⇒ [tex]\frac{1}{6}x-\frac{1}{2}x = 9+3[/tex]
⇒ [tex]\frac{-2x}{6}=12[/tex]
⇒[tex]\frac{-1}{3}x=12[/tex]
⇒ [tex]x=-36[/tex]
Hence we can conclude that the mistake is in the third step, the subtraction was done without taking LCM. The value of x is -36.
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