I confirm with the answer that k is the slope of the graph<span>. If the variables x and y vary directly when x = 3 and y = 15, then: a. Write an equation that relates x and y.</span>
For this case what you should do is follow the following steps:
1) factorize numerator and denominator of both expressions.
2) cancel similar terms
3) add both fractions by cross product
4) Rewrite the numerator and denominator.
Answer:
See attached image.
Answer:
1200 ml per hour
Step-by-step explanation:
To compute what rate is 300 ml over 15 mins as a rate of ml per hour, we do a rule of 3, using a variable x as that amount of ml we don't know yet. We should have everything in the same units, so instead of writing 1 hour we write 60 minutes:

Now we solve for x:



And so, now that we know the value of x, the rate we wanted to find is

Which is just 1200 ml per hour.
Answer:
225
Step-by-step explanation:
360 - 135 = 225