Answer:
x = 4
Explanation:
For this problem, we simply need to convert the words into the left hand side of the equation and solve for x:
The quantity of implies a grouping
x plus 20 is the quantity
And we want the quantity over 2 all equal to 3x:
( x + 20 ) / 2 = 3x
( x + 20 ) = 6x
20 = 5x
4 = x
And now we can check to see if x is correct by plugging back into the equation:
( x + 20 ) / 2 = 3x
( (4) + 20 ) / 2 ?= 3(4)
( 24 ) / 2 ?= 12
12 == 12
Therefore, we have shown the value of x to be equal to 4.
Cheers.