When you solve an equation, how do you know when to add and when to subtract? You may include an example if you need to.

please need help

Question

When you solve an equation, how do you know when to add and when to subtract? You may include an example if you need to.

please need help

jack1 · Answer

one of my teachers gave the best example (IMO) of:
imagine the equals sign is a see-saw
so what you always want to do is isolate a single ...item/variable/part, whatever you wsnt to call it

jack1 · Answer

ie 2x^3 - 5 = 13

anonymous · Answer

Well, you need to "cancel out". For example:5x+15=0. You have to cancel out positive 15 by subtracting it from both sides of the equation, so then you would have 5x=-15 and then you solve by "canceling out" the term of 5. 5 is being multiplied by x, so to get rid of it, you divide both sides of the equation by 5, so x=-3

jack1 · Answer

you want to isolate x, so use reverse BODMAS rules:

anonymous · Answer

oh ok thank you

anonymous · Answer

Your welcome :)