equations in math

solve for the variable
As long as you add, subtact, multiply or divide both sides you don't change the equation.



for instance

3x + 5 = 17

subtract the 5 from each side.

3x + 5 - 5 = 17 - 5

that gives you 3x=12

Now we would divide 3x by 3 to get x

3x/3 = 12/3

which results in x = 4


Don't forget that if you have a negative variable to make it positive

-x = 25 would mean that x = -25

Re: equations in math


the shelf has a length of 110cm ,width of 85cm and height of 25cm.The shelf has three planks having 5cm thickness.To polish the shelf the price is 20 paise per cm2 and to paint the shelf the price is 10 paise per cm2.what is the total expenses to polish and paint the surface area.

Very nicely explained, parados.
I would like to know though, if the lost guy got it now, or if he needs any more help.