Math 6 H Periods 1, 6 & 7

Review of Solving Combined Operations 8-5
Follow these general procedures to solving equations:

Step 1: Simplify each side of the equation

Step 2: If there are still indicated additions or subtrations, use the inverse operations to undo them

Step 3: If there are indicated multiplication or divisions involving the variable, use the the inverse operations to undo them

YOU MUST ALWAYS PERFORM THE SAME OPERATION ON BOTH SIDES OF THE EQUATION.

DO ONTO ONE SIDE WHAT YOU WOULD DO TO THE OTHER... hmmm... where have you heard that before??

Balance, balance , balance... it's all a balancing act!!


Solve the equation 3/2(n) + 7 = 22
subtract 7 FROM BOTH SIDES
(3/2)n = 15
Multiply BOTH SIDES by 2/3, the reciprocal of 3/2

(2/3)(3/2)n = 15(2/3)
simplify before you multiply out
n = 10

40 - (5/3)n = 15
There are two ways to solve this one
add (5/3)n to both sides
40 = (5/3)n + 15
then subtract 15 from BOTH SIDES
25 = 5/3(n)
Multiply both sides by 3/5, the reciprocal of 5/3
(3/5)25 = 5/3(n)(3/5)
Simplify before multiplying
15 = n

OR
40 - (5/3)n = 15
subtract 30 from both sides
- (5/3)n = 15 -40
need to ask yourself who wins? the negative... and by how much 25
- (5/3)n = -25

multiply by -3/5, which is the reciprocal of -5/3
(-3/5)-(5/3)n = -25(-3/5)
n = 15
we arrived at the same solution