Question

How to solve 3(x+3)=27

Answer 1

Explanation:

solving an equation is like finding out for a balance, why the contents of the 2 cups weigh the same.

to take away (or add) piece by piece the same weight from both sides to keep the balance, until you find the originally not obvious reason for the balance.

in our case e look for the value of x. everything else we know.

so, we try to sort between the types of terms (the ones with variables, the ones without variables, then maybe different variables if applicable and so on).

but we have to do it by keeping the balance.

so everything we change on one side, we also have change on the other.

3(x + 3) = 27

we could do now 2 different things.

we could multiply the bracket term and then see how to continue.

or we could divide both sides by 3 to get rid of the obscuring multiplication factor of the bracket term with the variable.

we still keep the variable on one side.

so, I suggest we do the second thing.

3(x + 3) = 27 | /3 both sides

x + 3 = 9

now we still have constant terms on both side.

let's get rid of the constants on the variable side.

how ? well, we need to subtract 3.

x + 3 = 9 | -3 on both sides

x = 6

hey, and we are finished !

x = 6 made the balance happen.

Answer 2

x=6

Explanation:

Basically you want to isolate x into a form x=... so you have to work your way backwards.

First, notice that there is an expression (x+3) that is multiplied by 3. Let's undo that. If we remove the 3, then the right hand side will also have to change. In fact, we can divide both sides by 3.

You then get (x+3) = 9.

Now, let's subtract 3 from both sides:

x+3 -3 = 9 -3

Which simplifies to x = 6.

So with the operations "divide left and right by the same" and "subtract the same left and right", you can simplify most equations.