Question 262205
your equation is:


3*(4*x-9) = x+100


simplify to get:


12*x - 27 = x + 100


so far you did good.


add 27 to both sides of this equation to get:


12*x = x + 100 + 27


you simplified this to get:


12*x = x + 127


so far you still did good.


you needed to get all the x's on one side of the equation.


you do that by subtracting x from both sides of the equation to get:


12*x - x = 127


simplify that to get:


11*x = 127


now you divide both sides of the equation by 11 to get:


x = 127 / 11 = 11.54545454


that should be your answer.


you confirm by substituting for x in the original equation.


original equation is:


3*(4*x-9) = x+100


substitute 11.54545454 for x to get:


3*(4*11.54545454 - 9) = 11.54545454 + 100


simplify to get:


3 * (37.18181818) = 111.54545454


simplify further to get:


111.54545454 = 111.54545454 confirming that the value calculated for x is good.


the numbers displayed on the calculator are usually rounded to the nearest 8 decimal places or thereabouts.


I used the internally stored numbers which are carried out to more digits than can be displayed.


If you just use the 8 or so decimal places displayed, your answer will be very close.


If you then round to the nearest 1 or 2 decimal places, your answer should be right on.