Lesson SOLVE AN EQUATION WITH PARENTHESES

This Lesson (SOLVE AN EQUATION WITH PARENTHESES) was created by by mathick(4)

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To solve an equation such as

5(x + 3) = 3x + 23,

the goal is to bring all the terms involving x over to the left side of the equals sign, and all the other terms over to the right.

What we have: expression with x's & numbers = expression with x's & numbers

what we want: expression with x's DISABLED_event_only= expression with numbers only

This equation has parentheses on the left, though, so we need to get rid of them first by distributing. After distributing,

5(x + 3) = 3x + 23

changes to

5x + 15 = 3x + 23.

Now we're ready to get all the x's on the left and the numbers on the right.

Subtract 3x from both sides (this brings all the x's to the left),

5x + 15 - 3x = 3x + 23 - 3x,

and simplify:

2x + 15 = 23.

Now subtract 15 from both sides (this brings all the numbers to the right).

2x + 15 -15 = 23 - 15,

and simplify:

2x = 8.

Now we got what we wanted! (expression with x's DISABLED_event_only= expression with numbers only)

The final step is to simplify. Dividing both sides by 2 gives

2x/2 = 8/2,

which simplifies to

x = 4.

The best way to remember all this is to try some out! Click on the link for step by step help working through any problem like this.

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