-2/3b+2/5=6/4/5

Question

i need the answer and how to work it out this is so hard. do u think u can help me

      

Answer 1

(-2/3) * b + (2/5) = (6/4) / 5

The direct mathematical approach is to see that the equation is in the form

m * b + n = k    where

m = -2/3;

n = 2/5;

k = (6/4) / 5 = (3/2) / 5 = 3/10  <==   I reduced the fraction to lowest terms. Let me know if you don't follow.

To solve for b, we want to isolate b to one side of the equation. The first step would be to subtract n on both sides of the equation so that you're left with only a constant multiplied by b on the left side:

m * b + n - n = k - n   ==>   m * b = k - n

Then, if you divide both sides of the equation by m, you've solved for b:

b = (k - n) / m

Now let's plug in the actual values of m, n, and k.

b = [(3/10) - (2/5)] / (-2/3);

b = [(3/10) - (4/10)] / (-2/3);

b = (-1/10) / (-2/3);

b = (1/10) / (2/3);

b = (1/10) * (3/2);

b = 3/20

To check our work, let's plug b = 3/20 back into our original equation and see if it's correct.

(-2/3) * b + (2/5) = (6/4) / 5

(-2/3) * (3/20) + (2/5) =? (6/4) / 5

(-2/3) * (3/20) + (2/5) = (-6/60) + (2/5) = (-1/10) + (2/5) = (-1/10) + (4/10) = 3/10 = (6/4) / 5

It works!

Answer 2

I am assuming that's 6 divided by 4 divided by 5....

1st step: deal with that weird "6 divided by 4 divided by 5"

6/4/5 is the same as (6*5)/4, which means it's equal to 30/4

Now, -2/3b+2/5=30/4

 

2nd step: try to isolate the b, subtract 2/5 from both side

-2/3b+2/5-2/5=30/4-2/5

-2/3b=30/4-2/5

 

3rd step: find common denominator for "30/4-2/5", let's make the denominator 20

-2/3b=150/20-8/20

-2/3b=142/20

 

4th step: I don't like that b being in the denominator, let's multiply both side by 3b

-2/3b*3b=142/20*3b

-2=426b/20

 

5th step: isolate that b! Multiply both side by 20

-2*20=426b/20*20

-40=426b

 

6th step (LAST step!): get the b!! Divide both sides by 426

-40/426=426b/426

-40/426=b

Yay!! :D If you need decimals, just plug it into a calculator!