2 Easy Math Questions for Algebra!!?

Question

Here are the two problems:

1. 7x/8 - 3x/5=11/2

2. 3x + 2 [1-3(x+2)] = 2x

If you don't mind, please show your work so it will be easier for me to solve my mistakes.....and if you do I'll give you the "Best Answer!!!"

Answer 1

Hi JRod.

NUMBER ONE

1. Here, you need to look at all the demoninators (numbers at the bottom of the fraction). 8, 5 and 2.

2. Find the LCM (lowest common multiple). - This is 40

3. This bits really hard to type so I will explain it.

After each term of the equation (eg. 7x/8) write x40

4. Then you can SIMPLIFY each term one by one.

for example for 7x/8 you would divide both by 8. 8 divided by 8= 1

40 divided by 8= 5 so now you get 7x TIMES 5. You have got rid of the fraction. Which ofcourse becomes 35X

do this for the next term 3x/5 TIMES 40. divide 5 by 5= 1. divide 40 by 5=8. simplifies to 3x TIMES 8. Which is 24x.

SO FAR WE HAVE 35X-24x=11/2TIMES 40

11/2 times 40 now simplify. 40 divided by 2 is 20. 2 divided by 2= 1. 11 times 20= 120

SO WE HAVE 35x-24x=120

(35-24= 11)

11x=120

x=10.10

Answer 2

I forget how to do the first one, but here is the second one,

3x+2[1-3(x+2)]=2x

3x+2[1-3x-6]=2x

3x+2-6x-12=2x

-3x-10=2x

-10=5x

-2=x

Answer 3

1. 7x/8 - 3x/5=11/2 <-- Multiply by 40 getting:

35x -24x = 220

11x = 220

x = 20

2. 3x + 2 [1-3(x+2)] = 2x

3x +2[1-3x-6] = 2x

3x +2 -6x -12 = 2x

3x -6x-2x = 12-2

-5x = 10

x = -2

Answer 4

1.) 7x/8 - 3x/5 = 11/2 (multiply both sides by least common denominator of 8, 5, and 2, which is 40)

35x - 24x = 220 (combine like terms)

11x = 220 (divide both sides by 11)

x = 20 <===ANSWER

2.) 3x + 2[1 - 3(x + 2)] = 2x (distributive property within parentheses)

3x + 2(1 - 3x - 6) = 2x (combine like terms within parentheses)

3x + 2(-3x - 5) = 2x (distributive property)

3x - 6x - 10 = 2x (combine like terms)

-3x - 10 = 2x (add 3x to both sides)

-10 = 5x (divide both sides by 5)

-2 = x

x = -2 <===ANSWER

Answer 5

1. Get common denominator

7x/8 - 3x/5=11/2 ....Multiply first fraction by 5/5 and second fraction by 8/8

(35x - 24x) / 40 = 11/2

11x / 40 = 11/2

Cross multiply

22x = 440...divide by 22

x = 20

2.  3x + 2 [1-3(x+2)] = 2x.......Distribute the 3 that is next to the parenthesis

3x + 2 [ 1 - 3x - 6 ] = 2x

3x + 2 [ -5 - 3x ] = 2x

3x - 10 - 6x = 2x

-3x - 10 = 2x

- 10 = 5x ...divide both sides by 5

-2 = x

Good luck to you !!

Answer 6

WOW!

Moonrose is good.

I thought I was going to get it quick and I didn't even explain the properties.

Answer 7

the first on is it equls 20 but i dont know the second one

35x    24x

___   ____     = 11

                         ----

      -                  2       11

                                   ---

40     40                        40   =  11

                                           ______

                                            2                so the answer is 20

                                                

      

Answer 8

do your own homework!!!