Jamal uses the steps below to solve the equation 6x – 4 = 8.
Step 1: 6x – 4 + 4 = 8 + 4
Step 2: 6x + 0 = 12
Step 3: 6x = 12
Step 4: StartFraction 6 x Over 6 EndFraction = StartFraction 12 Over 6 EndFraction
Step 5: 1x = 2
Step 6: x = 2
Which property justifies Step 3 of his work?
Answers
Jamal solves the equation 6x - 4 = 8
Step 1: 6x – 4 + 4 = 8 + 4
Step 2: 6x + 0 = 12
Step 3: 6x = 12
Step 4: 6x ÷ 6 = 12 ÷ 6
Step 5: 1x = 2
Step 6: x = 2
In Step 2, the result of addition of - 4 & +4 gives 0. In step 3, He adds 6x & 0
The property which justifies Step 3 of his work is Additive identity.
0 is a special number which when added to a number gives itself.
So, 6x + 0 = 6x
⇒6x + 0 = 12
⇒6x = 12
The same way, The property which justifies the Step 6 is, Multiplicative identity.
Any number multiplied by 1 gives itself.
So, 1 * x = x
⇒ 1x = 2
⇒ x = 2.
The above equation can be solved by using Transposition.
When changing a term from one side of the equation to the other
+ becomes -
- becomes +
× becomes ÷
÷ becomes ×
Given equation,
6x - 4 = 8
⇒ 6x = 8 + 4
⇒ 6x = 12
⇒ x = 12 ÷ 6
⇒ x = 2.
QUESTION :
Jamal uses the steps below to solve the equation 6x – 4 = 8.
Step 1: 6x – 4 + 4 = 8 + 4
Step 2: 6x + 0 = 12
Step 3: 6x = 12
Step 4: = StartFraction 6 x Over 6 EndFraction = StartFraction 12 Over 6 EndFraction
Step 5: 1x = 2
Step 6: x = 2
Which property justifies Step 3 of his work?
ANSWER :
- the addition property of equality
- the identity property of addition
- the multiplication property of equality
- the identity property of multiplication .