a. 2x/3 = 5

2x = 5 X 3

x = (5 X 3)/2

x = 15/2

= 7.5

b. 2x/3 = 1/4

2x = 1/4 X 3

x = (1/4 X 3) / 2

= 0.75 / 2 or 3/4 / 2

= 0.375

c. x/3 + 2/5 = 1/2

x/3 = 1/2 – 2/5

x = (0.5 – 0.4) X 3

= 0.3

When you take something to the other side of the = sign, you have to change the function. mulitplied becomes divided by, and vice versa. minus becomes plus and vice versa.

Sorry i didn’t keep it in fractions, it’s so much easier for me in decimals.

a. 2x/3 = 5

1. Multiply both sides of the equation by 3

(2x/3)(3) = 5(3)

2x = 15

2. Divide both sides of the equation by 2

2x/2 = 15/2

x=7.5

b.2x/3 = 1/4

You basically perform the same steps to solve this.

1. Multiply both sides by 3 to get 2x=3/4

2. Divide both sides by 2 to get x= 3/8

c. x/3 + 2/5 = 1/2

1. Find the Least Common Denominator of x/3 and 2/5

LCD = 30.

2. Multiply the numerators of x/3 and 2/5 by the number of times the denominator goes into the LCD.

3 goes into 30 ten times, so 10 times x is 10x/30

5 goes into 30 six times so six times 2 is 12/30

2 goes into 30 fifteen times so 15*1 is 15/30

10x/30 + 12/30 = 15/30

3. Subtract 6/15 from both sides of the equation

10x/30 = 3/30

4. Multiply both sides of the equation by 30.

10x = 3

5. Divide both sides of the equation by 10

x = 3/10 or 0.3

Check the work and just remember to isolate the variable.

3(2x/3)=5*3 to get 2x=15

now, you just need to divide both sides by 2, and simplify, leaving you with

2x/2=15/2 which becomes x=15/2 which simplifies to x=7 1/2

2x = 5 x 3

x = 7 1/2

b. 2x/3 = 1/4

2x = 3/4

x = 1 1/2

c. x/3 + 2/5 = 1/2

x/3 = 1/2 + 2/5

x = 2 7/10

1)

2x/3=5

How much does “X” need to be to make that work?

we sovle for “x” to determine that answer.

2x/3=5

3*(2x/3)=3*5

we can rewrite that

2x*(3/3)=15

since 3/3=1

2x*1=15

or

2x=15

now let’s divide both sides by 2

2x/2=15/2

x*(2/2)=7.5

x*1=7.5

x=7.5

2)

2x/3=1/4

2x/3*3= 3*(1/4)

2x=3/4

2x/2=(3/4)/2

x=3/8

c)

x/3+2/5=1/2

x/3+2/5-2/5=1/2-2/5

x/3=1/2-2/5

(x/3)*3=3*(1/2-2/5)

x = 3*(1/2-2/5)

or x=3*(1/10)=3/10

A previous answerer already gave a good answer so I won’t repeat it. But, you really have to learn this stuff on your own, ’cause it is going to come back to haunt you again and again and again. And it will not get any easier with each passing year.

Do you want fries with that?