Answer: 16 hours
Step-by-step explanation:
The two equations are:
840 + 17x
and
760 + 22x
with x being the amount of hours
840 + 17x = 760 + 22x
-760
80 + 17x = 22x
-17x
80 = 5x
/5
16 = x
840 + 17(16) = 1,112
760 + 22(16) = 1,112
Yes, it’s D because you would have want to compare both fractions by making them have the same denominator. Since 60 is the least common denominator for 10 and 12 (the denominators), you would convert the fractions by multiplying the numerator and denominator of 5/10 by 6 to get 60. 5/10 would turn into 30/60. Then you would multiply 6/12 both by 5, and then it would turn into 30/60. Now that you have equal fractions, you can guess that they are the same. Therefore, 30/60=30/60! An easier way of doing it would be just simplifying them into 1/2 and comparing them + seeing that they are both 1/2. Hope this helps!
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Caramelatte
For this case we have the following system of equations:

To solve, we clear "x" from the second equation:

We substitute "x" in the first equation:

We clear the value of the variable "y":

We look for the value of the variable "x":

Thus, the solution of the system is given by:

Answer:

Option D
The answer is a equals 6.