basic algebra help again??

Question

ok i know how to do this, but if your changing the fractions into whole numbers by the LCD, for this one how would you do it because it has parentheses?

3/4(4/5x-2)=11/4

i want to know how to do it by changing the fractions into whole numbers first

Answer 1

Multiply both side by 4.
3(4/5x-2)=11
12/5x-6=11
12/5x=17
Multiply both side by 5.
12x=85
x=85/12 or 7 1/12

Answer 2

You have 4, 5, and x in the denominator. So multiply both sides by the common denominator 20x (make a mental note that if you then get x=0, it could be wrong). Clear the parenthesis by using the distributive law, and after canceling x's (once again, can't do if x = 0), you get an equation without parentheses or fractions. Then you can move x terms to one side, constants to the other, combine and divide to get the answer. If it turns out to be 0, there is no solution, otherwise you get the solution to the equation, which should be 12/85.

I see that other answerers are getting 85/12 as the answer. The problem is the term 4/5x. Although multiplication and division are of equal rank, so you would go from left to right, there is the compelling vision of seeing 5x as a term, so that the fraction is 4 divided by 5x. It helps in a case like this to use a symbol for multiplication, as in 4/5*x, or to use parentheses, as 4/(5x) or (4/5)x, as the case may be.

Answer 3

The order of operations is PEMDAS = parenthesis, exponents, mult, division, addition, subtraction.

Start by looking inside the parenthesis. There is nothing we can do in there yet so we move on.

Now the next operation in PEMDAS is multiplication (there are no exponents). To isolate x, we need to first get rid of the denominators on both sides, multiply by 4 on both sides of the equation --> 3(4/5x - 2) = 11.

Next in PEMDAS is divide so to isolate x, we need to divide on both sides by 3 --> 4/5x - 2 = 11/3.

Next to isolate x, we must add 2 to both sides --> 4/5x = 11/3 + 2

Now we use the LCD to add fractions. The least common denominator is 3 so we multiply both fractions by 3/3 (this is allowed because it is equivalent to multiplying by 1 so it doesn't change the equation --> 4/5x = (3/3)*(11/3) + (3/3)*2 -->
4/5x = 11/3 + 6/3 = 17/3.

Now to convert the fractions to whole numbers, we can multiply both sides by the LCD again, which is 5*3 = 15 -->
3*4X = 5*17 --> 12x = 85

To isolate x, we must divide by 12 to get x = 85/12. To check this, use a calculator and plug 85/12 in for x into the left side of the equation and you will get 11/4 or 2.75.

Answer 4

Well, you can't change a fraction into a whole number. Whole number are 0, 1, 2, 3, etc.

But multiple 3/4 and 4x/5 then subtract that from (3/4 * 2). Solve for x.

X=85/12

Answer 5

if you meant (3/4)((4/5)x-2) = 11/4, then you would multiply both sides by 4*5 = 20. That will eliminate all the denominators.

Answer 6

3/4 * (4/5 * x - 2) = 11/4
.....multiply by 4 to both sides

3 * (4/5 * x - 2) = 11
.....multiply by 5 on both sides

3 * 5 * (4/5 * x - 2) = 11 * 5
.....distribute the 5

3 * (4x - 10) = 55

The answer comes out to 85/12 or about 7.09

Answer 7

just dont be afraid of fractions :D

3/4(4/5x-2)=11/4
(4/5x-2)=(11/4)/(3/4)
(4/5x-2)=11/3
4/5x=11/3+2
4/5x=(11+6)/3
4/5x=17/3
x=(17*5)/(4*3)
x=85/12

Answer 8

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Answer 9

okay lets see.. LCD = 20 .. so it would be 15(16x-40)=55 i think then you need to get rid of the parentheses .. so it would be 240x-600=55 . then you need to solve for x .... 240x=655 ........ x=2.7291666666666666667

Answer 10

first 3/4=0.75
0.75*(4/(5x-2))=2.75
4/(5x-2)=2.75/0.75
4/(5x-2)=3.666666
5x-2=3.66666666*4
5x-2=14.66666666
x=3.333333333
x=3 and 1/3
x=10/3