7/9 = 0.77777778
honestly i just googled this
9t-6-6t=6 -- add 6 to both sides
9t-6t=12 -- combine like terms
3t=12 -- divide by 3
t=4
Y= 5.91 yup that’s the answer
Answer: Interval = [103,∞)
Explanation :
A medicine become ineffective if its temperature ever reaches 103 degrees Fahrenheit or more .
So, Interval becomes [103,∞)
i.e. semi-open or semi-closed interval as it includes 
So, we used closed brackets i.e. square brackets and
For '∞' we always use open brackets only.