Jessica Said:

Algebra Fractions Test Tomorrow Help Please?

We Answered:

Easiest way ever, depending, would either be to turn them into decimals (sometimes you cannot do this!) Otherwise you have to find a common denominator.

1/2 + 1/3, for example. This would be a bad one to turn into decimals because 1/3 is irrational (it goes on forever as 0.3333...) So a common denominator is the way to go!

the LCM (least common multiple) of 2 and 3 (the denominators) is 6. so 1/2 = 3/6, because to get from 2 to 6 you'd multiply 2 by 3, so do the same for the numerator (1 x 3) and get 3. Apply the same logic to 1/3 and you'll get 2/6. Once again, 3 x 2 = 6, so 1 x 2 = 2. 2/6.

Now add them. 2/6 + 3/6 = 5/6. You cant simplify 5/6, so it remains that way. 1/2 + 1/3 = 5/6! Want it in decimal form? Divide 5 by 6, because FRACTIONS ARE DIVISION.

:)

Jim Said:

Algebra/Fractions???

We Answered:

1) x+1/2=3/3/4 what is x?
x+1/2 = 4
x=3.5

2) 3/1/5+1/2c=20
15 +c/2 =20
c/2=5
c=10

3) 1/10*-1=19 ?????

a)five times a number decreased by twelve equals thirty-three
5x-12 =33
5x=45
x=9

b) twelve divided by a number, and decreased by 4 equals two
(12/x) -4 =2
12/x=6
12=6x
x=2

c) six times a number increased by six equals 33
6x +6=33
6x=27
x=9/2

Jill Said:

How do you clear the fractions in an algebra problem by multiplying both side of the equation by the LCD of?

We Answered:

Consider a fraction such as:
5/6

If you multiply it by 6:
6 × 5/6
= 6/1 × 5/6
= 1/1 × 5/1
= 5

In fact, any number that has 6 as a factor will cancel out the 6 also.

If you multiply an equation by a number that is a common multiple of the denominators (the lowest one, ideally; the LCD), you get rid of all the fractions.

The formal way to find the LCD is to find the factors of the denominators. For an example:

3/4 + x/2 = 1/6(x - 2)

The denominators (and their prime factors) are:
2 = 2
4 = 2·2
6 = 2·3

You need the maximum number of 2s found in just one (from the four here) and the maximum number of 3s (one).
2·2·3 = 12

Of course, you can usually find the LCD for two and then find the LCD for that number and the next fraction. e.g. the LCD of 1/2 and 1/4 would be 4, then if you do that for 4 and 6, you get 12.

If you multiply by the LCD, you get:
12[ 3/4 + x/2 ] = 12 [ 1/6(x - 2) ]
9 + 6x = 2(x - 2)

Note that you just divide the 12 by the denominator and then multiply it by what is left. For example, 12 divided by 4 gives 3 so you multiply by the 3 of 3/4 and you get 9.

Of course, you don't really have to do this step to get rid of fractions, as you can just work with fractions normally, but a lot a people prefer to get rid of them

Amanda Said:

What do you do next in algebra I after clearing fractions?

We Answered:

If there are parentheses, then get rid of them with distributive property, otherwise got straight to combining like terms

Kirk Said:

How do you add algebra fractions with complicated denominators?

We Answered:

[4 / (x - 4)] + [3 / (x + 3)]

Ok, so you want them to both have the same denominator in order to add. First you have to think to yourself what is the least common denominator in this case. Well we have (x - 4) in one denominator and we have (x + 3) in the other. This means that the least common denominator is (x-4)(x+3) in this case. So you need to get both of these to have that denominator. Look at 4 / (x - 4). Multiply the top and the bottom of this fraction by (x + 3) and you'll have:
[4(x + 3) / (x - 4)(x + 3)] + [3 / (x + 3)]

Do the same with 3 /(x + 3) except multiply the top and bottom by (x - 4):
[4(x + 3) / (x - 4)(x + 3)] + [3(x - 4) / (x - 4)(x + 3)]

Now you can add them:
[4(x + 3) + 3(x - 4)] / [(x - 4)(x + 3)]

Distribute:
[4x + 12 + 3x - 12] / [(x - 4)(x + 3)]

Combine like terms:
[7x] / [(x - 4)(x + 3)]

They may also want you to FOIL the denominator:
[7x] / [x² - x - 12]


Hope it helps

Gordon Said:

Algebra fractions?

We Answered:

Factor out as much common factor as you can:
G(m1 m2/ x²) - G(m1 m2/ 3x²)
= G(m1 m2/ x²) ( 1/1 - 1/3 )

Now take a common denominator 3x²...
= G(m1 m2/ 3x²) ( 3 - 1 )
= (2/3) G(m1 m2/ x²)