Answer:
Instrumental understanding – having a mathematical rule and being able to apply and manipulate it. Relational understanding – having a mathematical rule, knowing how to use it AND knowing why it works.
Step-by-step explanation:
Instrumental understanding involves “memorising which problems a method works for and which not, and also learning a different method for each new class of problems” (Skemp 1987, p. 159), is a desire to know “some kind of rule for getting the answer” (p. 155) so that a student can “latch on it and ignore the rest”
Answer:
Option A. is the right choice.
Step-by-step explanation:

Best Regards!
The answer is both all real numbers less than 0 and all real numbers greater than 0
3.4/20 divided by 20/20
=.17
The cost per ounce is 17¢
Let x represent the number.
.. x^2 +x = 2
.. x^2 +x +1/4 = 9/4 . . . . add 1/4 to complete the square
.. x +1/2 = ±3/2 . . . . . . . .square root
.. x = -2, 1
Numbers meeting that requirement are -2 and 1.