Solution - Adding, subtracting and finding the least common multiple

Reformatting the input :

Changes made to your input should not affect the solution:

(1): "0.7" was replaced by "(7/10)". 2 more similar replacement(s)

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                28-(3/10)*y-((7/10)*y-12)=0 

Step by step solution :

Step  1  :

             7
 Simplify   ——
            10

Equation at the end of step  1  :

        3        7
  (28-(——•y))-((——•y)-12)  = 0 
       10       10

Step  2  :

Rewriting the whole as an Equivalent Fraction :

 2.1   Subtracting a whole from a fraction

Rewrite the whole as a fraction using  10  as the denominator :

          12     12 • 10
    12 =  ——  =  ———————
          1        10   

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

 2.2       Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

 7y - (12 • 10)     7y - 120
 ——————————————  =  ————————
       10              10   

Equation at the end of step  2  :

           3          (7y - 120)
  (28 -  (—— • y)) -  ——————————  = 0 
          10              10    

Step  3  :

             3
 Simplify   ——
            10

Equation at the end of step  3  :

           3          (7y - 120)
  (28 -  (—— • y)) -  ——————————  = 0 
          10              10    

Step  4  :

Rewriting the whole as an Equivalent Fraction :

 4.1   Subtracting a fraction from a whole

Rewrite the whole as a fraction using  10  as the denominator :

           28     28 • 10
     28 =  ——  =  ———————
           1        10   

Adding fractions that have a common denominator :

 4.2       Adding up the two equivalent fractions

 28 • 10 - (3y)     280 - 3y
 ——————————————  =  ————————
       10              10   

Equation at the end of step  4  :

  (280 - 3y)    (7y - 120)
  —————————— -  ——————————  = 0 
      10            10    

Step  5  :

Adding fractions which have a common denominator :

 5.1       Adding fractions which have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

 (280-3y) - ((7y-120))     400 - 10y
 —————————————————————  =  —————————
          10                  10    

Step  6  :

Pulling out like terms :

 6.1     Pull out like factors :

   400 - 10y  =   -10 • (y - 40) 

Equation at the end of step  6  :

  40 - y  = 0 

Step  7  :

Solving a Single Variable Equation :

 7.1      Solve  :    -y+40 = 0 

 Subtract  40  from both sides of the equation : 
                      -y = -40
Multiply both sides of the equation by (-1) :  y = 40

One solution was found :