Easy Algebra Step-by-Step

(Marvins-Underground-K-12) #1

Algebraic Expressions 71


If an opposite (−) symbol immediately precedes parentheses that enclose an
algebraic expression, remove the parentheses and the opposite symbol and
rewrite the algebraic expression, but with all the signs changed.

Problem Simplify −−⎛ +−

⎛⎛⎛⎛


⎝⎝


⎛⎛⎛⎛ ⎞



⎞⎞⎞⎞


⎠⎠


8 5 ⎞⎞⎞⎞


2


xy^3227
x

.


Solution
Step 1. Remove the parentheses and the oppo-
site symbol and rewrite the expression,
but change all the signs.

−−⎛ +−



⎛⎛⎛⎛


⎝⎝


⎛⎛⎛⎛ ⎞



⎞⎞⎞⎞


⎠⎠


8 5 ⎞⎞⎞⎞=−+


2


27 8


5


2


xy^323227
x

xy
x

If a minus (−) symbol immediately precedes parentheses that enclose an
algebraic expression, mentally think of the minus symbol as “+−,” meaning
“add the opposite.” Then remove the parentheses and rewrite the algebraic
expression, but change all the signs.

Problem Simplify 10 −() 373 3277 ++ 22.

Solution
Step 1. Mentally think of the minus symbol as “+−.”

10 +−() 3 3277777 2 ++ 22
Do this mentally.

  


Step 2. Remove the parentheses and rewrite the algebraic expression, but
with all the signs changed.

10 −() 3373277 ++ 22 = 10 − 373 xx^3277 − 2 x

If a number immediately precedes parentheses that enclose an algebraic
expression, apply the distributive property to remove the parentheses.

P


P


P


−−⎛ +−
⎝⎜

⎛⎛
⎝⎝


⎠⎟

⎞⎞
⎠⎠

8 5 ≠+−
2

27 8 5
2

xy^323227
x

y
x

.

Change all the signs, not just the fi rst
one. This mistake is very common.
Free download pdf