Answer:
Step-by-step explanation:
Subtraction is not commutative. For example, 4 − 7 does not have the same difference as 7 − 4. The − sign here means subtraction.
However, recall that 4 − 7 can be rewritten as 4 + (−7), since subtracting a number is the same as adding its opposite. Applying the commutative property for addition here, you can say that 4 + (−7) is the same as (−7) + 4. Notice how this expression is very different than 7 – 4.
18. equivalent
16x5 does equal 10x8
19. equivalent
13-0 does equal 0
20. Not equivalent
12-2 doesn’t not equal 7-3
For all three of these equations you have to use PEMDAS (systems of equations) so first you solve everything that’s in parentheses, then any exponents, followed by multiplication,division,addition, and lastly subtraction. You MUST follow that order to get the correct answer.
Let's look at each answer choice's words per minute:
A) 320/8 = 40
B) 600/12 = 50
C) 350/10 = 35
D) 225/5 = 45
The fastest is 50 words/min which is B