how do evaluate or simplify algebra expressions??

Question

can u please give me examples and explain??

Answer 1

http://www.mathleague.com/help/algebra/algebra.htm

Answer 2

Evaluate means to "find the value" of.

To "evaluate" an expression means to find its value, or to solve it. The first rule to learn about algebra is "what to do when." The order in which an expression's operations are done can completely change the answer.

When evaluating an algebraic expression, first look for the symbols which show the innermost work. That can be expressed by use of parentheses or brackets. If BOTH parentheses and brackets are present, the parentheses are usually the innermost and should be worked first.

Here is an example:

24 + [46 - (2 X 11)]

24 + [46 - 22]

24 + 24

48

http://www.lessontutor.com/eesA1.html

Simplify means to make more simple.

Simplifying Equations
To find a solution for an equation, we can use the basic rules of simplifying equations. These are as follows:
1) You may evaluate any parentheses, exponents, multiplications, divisions, additions, and subtractions in the usual order of operations. When evaluating expressions, be careful to use the associative and distributive properties properly.

2) You may combine like terms. This means adding or subtracting variables of the same kind. The expression 2x + 4x simplifies to 6x. The expression 13 - 7 + 3 simplifies to 9.

3) You may add any value to both sides of the equation.

4) You may subtract any value from both sides of the equation. This is best done by adding a negative value to each side of the equation.

5) You may multiply both sides of the equation by any number except 0.

6) You may divide both sides of the equation by any number except 0.

Hint: Since subtracting any number is the same as adding its negative, it can be helpful to replace subtractions with additions of a negative number.

Example:

This problem illustrates grouping like terms and dealing with subtraction in an equation.

Solve x - 12 + 20 = 37.

Replacing the -12 with a +(-12), we get

x + (-12) + 20 = 37.

Since addition is associative, the two like terms (the integers) may be combined.

(-12) + 20 = 8

The left side of the equation becomes

x + 8 = 37.

Now we may subtract 8 from each side of the equation, (we will actually add a -8 to each side).

x + 8 + (-8) = 37 + (-8)

x + 0 = 29

x = 29

We can check this solution in the original equation:

29 - 12 + 20 = 37

17 + 20 = 37

37 = 37 so our solution is correct.

http://www.mathleague.com/help/algebra/algebra.htm

Read this for examples.......
http://mathforum.org/library/drmath/view/52280.html

http://www.wtamu.edu/academic/anns/mps/math/mathlab/beg_algebra/beg_alg_tut4_vari.htm

Answer 3

To evaluate is to solve for the value of the unknown (or variable) to satisfy the given equation.

Example :
Evaluate

1) 3 + a = 15
a = 15-3
a = 12

Also, to evaluate is to find the answer as a result of a given operation

Example
Evaluate
4 x 5 =
4 x 5 = 20

To simplify is only to make the term or terms to its simplest form. There is no solving involved.

Examples
Simplify
1) 2/4 ==> 2/4 = 1/2

2) 6x^2y^3 / 2xy^2 ==> 3xy

Answer 4

Add or subtract things that are the same.
Example
5 oranges + 2 apples + 3 oranges =
8 oranges + 2 apples
Example
3x² + 2y + 6 z + 5 x² + 9y
= 8 x² + 11 y + 6z
Example
7a² + 8t + 4w - 3a² - 2t
4a² + 6t + 4w
Hope these examples are of use.