
Jordan K. answered 05/23/13
Nationally Certified Math Teacher (grades 6 through 12)
Hi Lakeyshia,
Let's begin by writing our equation: 3(4z - 1) - 2(2 + 8) = 3(2 + 1)
First, we'll combine all like numeric terms in the parentheses on both sides of the equation:
3(4z - 1) - 2(10) = 3(3)
Next, we'll do the multiplication operation indicated by the paretheses for each term on both sides of the equation (for the 1st parentheses we'll distribute (multiply) the 3 outside the parenthesis by each term inside the parenthesis):
12z - 3 - 20 = 9
Next, we'll combine our like numeric terms on the left side of the equation:
12z - 23 = 9
Next, we'll get rid of the -23 on the left side of the equation by doing the opposite operation of addition (adding 23 to both sides of the equation):
12z = 32
Next, we'll get rid of the 12 in front of the z on the left side of the equation by doing the opposite operation of division (dividing both sides of the equation by 12):
z = 32/12
Finally, we'll reduce the fraction value for z by dividing both numerator and denominator by the largest factor common to both 12 and 32 (we'll divide both numerator and denominator by 4):
z = 8/3 (our solution)
Thanks for submitting your question.
Regards, Jordan.