Question

Solve & Justify 3(5x + 1) = 18x

Answer 1

Answer:

x=1

Step-by-step explanation:

First you distribute the 3 to 5x and 1 to get 15x+3=18x

Then you subtract 15x from 18x and get 3x

Lastly you divide 3 by 3 to separate the 3 and x and get x=1.

Answer 2

Answer:

x=30

Step-by-step explanation:

          3

Simplify   —

           5

 3          

 (— • x) -  18  = 0  

  5          

STEP

  Subtracting a whole from a fraction

Rewrite the whole as a fraction using  5  as the denominator :

         18     18 • 5

   18 =  ——  =  ——————

         1        5    

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 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:

3x - (18 • 5)     3x - 90

—————————————  =  ———————

      5              5  

Pull out like factors :

  3x - 90  =   3 • (x - 30)

 3 • (x - 30)

 ————————————  = 0  

      5      

When a fraction equals zero ...

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

 3•(x-30)

 ———————— • 5 = 0 • 5

    5    

Now, on the left hand side, the  5  cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

  3  •  (x-30)  = 0

Solve :    3   =  0

This equation has no solution.

A a non-zero constant never equals zero.

  Solve  :    x-30 = 0  

Add  30  to both sides of the equation :  

                     x = 30

One solution was found :

x = 30