Answer:
What is the question?
Step-by-step explanation:
Answer:
A Exactly one solution
Step-by-step explanation:

Putting y=0 at second equation, we have

The unique solution is 
Answer:
Hi there, I believe the answer to this equation is: 2.8
Step-by-step explanation:
Subtract 7 on both sides so
5n+7=21-7
you are left with 5n=14 you need to get n by itself so divide 5 on both sides.
5n/5 = 14/5
n=2.8
Hope this is correct :)
Have a great day
The <em><u>correct answer</u></em> is:
7.8 × 10⁷
Explanation:
To write a number in scientific notation, we want the decimal behind the first non-zero digit in the number. The first non-zero digit in 78 is 7; this means we want 7.8. In order to have the decimal point behind the 7, we need to move the decimal 7 places. This is the exponent of 10 in our scientific notation, which gives us
7.8 × 10⁷