Answer:
Depending on how the input of each function defined,
- The first choice
, - The third choice
- The fourth choice
might be functions.
Step-by-step explanation:
A function between two sets (domain and range) should
- be defined for all elements in the domain, and
- map each element from the domain to exactly one element in the range.
The second choice can't be a function since the element 
from the domain is mapped to more than one element in the range.
Keep in mind that a function should be defined for all elements in its domain. For the first relation to be a function, its domain needs to be 
. Similarly, the domain for the third and fourth relations should be 
and 
The slope is -9/7. I don’t have an explanation because I used an online calculator but that’s the answer in case you don’t have to show work.
Answer:
2.4 hr. = time working together
Step-by-step explanation:
Let x = time working together
x/6 = work done by Martin
x/4 = work done by Victor
Martin's part + Victor's part = 1 jog done
x/6 + x/4 = 1 Multiply thru by 12
2x + 3x = 12
5x = 12
x = 2.4 hr.
Answer: See explanation
Step-by-step explanation:
7x - 2(x + 3y) + 3y
= 7x - 2x - 6y + 3y
= 5x - 3y
Will got 5x + 9y because he didn't multiply the values in the bracket by the minus sign outside the bracket. He multiplied the values by +2 rather than -2. This resulted in the wrong answer that he got.
