Solving a 2 step equation Involving Rational Numbers

by Monica Marie
(Virginia)

2/3 = -1 5/9 + 5/8x

I'm getting stuck on finding the common denominator with a mixed number to get this answer. Help!!



Karin from Algebra Class Says:

The first thing that you must do is convert the mixed number to an improper fraction.

-1 5/9 = -14/9 as an improper fraction.

Then you can begin solving by getting rid of the fraction. The least common multiple for 3, 9, and 8 is 72. Therefore, you must multiply all terms by 72.

722/3 = 72-14/9 + 5/8x

48 = -112 + 45x

Now that you don't have any fractions, it's much easier to solve this 2 step problem.

Step 1: Add 112 to both sides.

48 + 112 = -112 + 112 + 45x

160 = 45x

Step 2: Divide by 45 on both sides

160/45 = 45x/45

32/9 = x

Step 3: Then substitute to check your answer.

2/3 = -14/9 + 5/8(32/9)
2/3 = 2/3

I hope this helps,
Karin

Comments for Solving a 2 step equation Involving Rational Numbers

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Nov 07, 2013
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starstarstarstarstar 		help NEW
by: Anonymous

3/B + P/4 = 3/4
Jan 28, 2013
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starstarstarstarstar 		HELP ME!!!
by: Anonymous

i need help on this problem
1 and 3 5ths-1 3rd y = -1 and 8 9ths
Sep 12, 2012
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starstarstarstarstar 		rational numbers and equations
by: Anonymous

i need help on 32x17/24
Aug 30, 2012
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starstarstarstarstar 		Two step equations
by: Anonymous

I need help on this problem z + 9 divided 4 = 2.1
Jun 28, 2012
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starstarstarstarstar 		help
by: Anonymous

i need help on this now. 1.3-5r=7.4
May 16, 2012
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starstarstarstarstar 		help on homework
by: sierra

i need help on this equation 2/3 x + 3/9 = 5/9 find x?
Jan 15, 2012
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starstarstarstarstar 		helpful
by: rakayla

this website was very helpful i am doing a little better in math and my teacher sees progress and a change in me and so will my parents
Nov 21, 2011
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starstarstarstarstar 		Two Step Equation
by: Anonymous

What is 1/3x-5=30

____________________________________________________

Karin from Algebra class Says:

For the equation, 1/3x - 5 = 30, I would start by adding five to both sides:

1/3x - 5+5 = 30+5
1/3x = 35

Now you can isolate x by multiplying both sides by 3.

3(1/3x) = 35(3)
x = 105

Hope this helps,
Karin
Oct 04, 2011
Rating
starstarstarstarstar 		Two Step Equation
by: Anonymous

5/9+x=2/3

____________________________________________________

Karin from Algebra Class Says:

5/9 + x = 2/3

In this problem, we have two fractions. We need to multiply all terms by the least common multiple (of the denominators), and this will get rid of the fractions.

The least common multiple of 9 and 3 is 9. Therefore, we will multiply all terms by 9.

9[5/9 + x] = 2/3(9)
5+ 9x = 6

Now solve the two step equation.

Subtract 5 from both sides.

5-5 +9x = 6-5

9x = 1

Divide by 9 on both sides

9x/9 = 1/9

x = 1/9.

Check your answer by substituting.

5/9 + 1/9 = 6/9

6/9 can be simplified to 2/3. Therefore, my answer is correct.

x = 1/9.

Hope this helps!!!
Sep 09, 2011
Rating
starstarstarstarstar 		I'm stuck!!!!
by: Anonymous

Do u know what is 3x/4-1/2=4
what does x=?

____________________________________________________

Karin from Algebra Class Says:

S

For the problem:
3x/4 - 1/2 = 4

First get rid of the fraction by multiplying by 4.

4[3x/4-1/2] = 4(4) Notice that I multiply all terms by 4 on both sides!

3x - 2 = 16

Now solve as a two step equation by first adding 2 to both sides.

3x-2+2 = 16+2
3x = 18

Now divide by 3 on both sides.
3x/3 = 18/3

x = 6

Check by substituting 6 into the original equation:

(3*6/4) - 1/2 = 4
4=4

The final answer is x = 6.

The key is getting rid of the fraction first!!

Hope this helps,
Karin
Sep 01, 2011
Rating
starstarstarstarstar 		Solving Equations with Rational Numbers
by: Anonymous

1.5d=3/8

____________________________________________________

Karin from Algebra Class Says:

For the problem:

1.5d = 3/8

This problem seems more confusing because you have decimals and fractions. Decimals are a little easier to work with than fractions, so I would start by multiplying all terms by 8 to get rid of the fraction.

8(1.5d) = 3/8(8)
12d = 3 Now you don't have decimals or fractions!

To solve, subtract 12 from both sides:
12d/12 = 3/12

d = 1/4 (3/12 simplified is 1/4)

Check by substituting:
1.5(.25) = .375 which is 3/8
.375 = .375

The final answer is d = 1/4 or d = .25

Hope this helps,
Karin
Jun 09, 2011
Rating
starstarstarstarstar 		Math iz hard
by: Anonymous

good very good

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