i need help with this math problem

Question

5-0.1(x-30)=18+0.05(x+100)

 

the decimals make it extremely difficult 

Answer 1

I recommend CLEARING DECIMALS as a first step. If the entire equation were multiplied by 100 on each side, the decimal points would all go away and you would have only integers to distribute.  Then at the end you would, in the worst case, have a rational solution (and in this case, it would in fact be an integer solution).

 

The same answer that Marlene and Noyam gave would be obtained, naturally.

Answer 2

Multiply the values in the perenthises with the number outside then solve for x.

5 - 0.1x + 3 = 18 + 0.05x + 5

8 - 0.1x = 18 + 0.05x + 5

8 - 23 = 0.15x

-15 = 0.15x

x = -100

Answer 3

Hi Seth.

 

Let's take this one step at a time.

 

5 - 0.1(x-30) = 18 + 0.05(x+100)

 

Let's distribute the decimal first

5 - 0.1x + 3 = 18 + 0.05x + 5

 

Now combine the constants on each side of the equal sign

8 - 0.1x = 23 + 0.05x

 

Subtract 8 from both sides

-0.1x = 15 + 0.05x

 

Subtract 0.05x from both sides

-0.15x = 15

 

Divide both sides by -0.15

x = -100

 

To double check, substitute -100 for x in the original equation

5 - 0.1(-100-30) = 18 + 0.05(-100+100)

5 - 0.1(-130) = 18 + 0.05(0)

5 - (-13) = 18 + 0

5+13 = 18 √