Answer:
The correct option is (d)-He wrote commutative instead of associative in Step 2.
Step-by-step explanation:
Commutative property: 
Associative property: 
Now consider the provided expression.
(6.2 − 1.6) − 4.4 + 7.8
Step 1
(6.2 − 1.6) − 4.4 + 7.8
Step 2 Use Associative property
6.2 + (−1.6 − 4.4) + 7.8
Step 3: Simplify
6.2 − 6 + 7.8
Step 4: Use commutative property
14 − 6
Step 5: Simplify
14 − 6 = 8
Hence, the wrong step is step 2. He wrote commutative instead of associative in Step 2.
Therefore, the correct option is (d)-He wrote commutative instead of associative in Step 2.
It would be -70. Your welcome
Answer:
x = ± 
Step-by-step explanation:
Given
2x² - 9 = 11 ( add 9 to both sides )
2x² = 20 ( divide both sides by 2 )
x² = 10 ( take the square root of both sides )
x = ± ← exact solutions
The answer is that the ratio of a to c is 9/5
156 minutes.
To find this, remember that an hour has sixty minutes. With this information, it is also given that there are two hours, thus meaning that we have to multiply sixty by two. This will give you 120. Next, you need to figure out the 3/5's portion of an hour. To find 1/5 of an hour, simply divide sixty by five. With that, you get the answer of 12. But because it says 3/5, you need to multiply 12 by 3, giving you 36. Finally, you add 36 to 120 to get the final answer of 156.
Hope this helps!
