Answer: b. y=2x+20; x is any real number greater than or equal to 0, and y is any real number greater than or equal to 20.
Step-by-step explanation:
Hi, to answer this question we have to analyze the information given:
time spent on history homework: 20 minutes
time spent on each math problem: 2 minutes
math problem : x
total time spent :y
So, we have to multiply each math problem (x) by the time spent on each math problem and add the 20 minutes spent on history homework.
The expression obtained is equal to the total time spent
Mathematically speaking:
y=2x+20
x can be any real number greater than or equal to 0, ( it would be 0 if there aren't any math problems)
and y is any real number greater than or equal to 20. ( 20 minutes is the minimum time spent if there aren't any math problems)
To make y the subject, we must move everything to one side and y on the other.

Good day and I hoped that helped!
0+0=0 0+0=0+0
They are all addition, and they are all 0, and since 0 equals nothing, the sum is equivalent to 0!
Well if you are looking for the profit margin we need how much is was when she bought it, because it doesn't say, you can't say It's a increase or a decrease, so you could say this is a investment.
But considering you put this under mathematics I assume there is more to this question you forgot to post.
Answer:
<u>The answer is option C. 6a-7</u>
Step-by-step explanation:
Given that
5(3a-1)-2(3a-2)=3(a+2)+v
Solve for v
∴ v = 5(3a-1)-2(3a-2) - 3(a+2)
∴ v = 15a - 5 - 6a + 4 - 3a - 6
∴ v = 15a - 6a - 3a - 5 + 4 - 6
∴ v = 6a - 7
<u>So the answer is option C. 6a-7</u>