The slope of this line is 4/5
The answer is <span>The liquid must be in the cooler fewer than 10 minutes.
</span>
Let:
m - the number of minutes the liquid is in the cooler.
a - the starting temperature
The function is:
f(m) = a - 3 * m (Since the temperature decreases by 3°F each minute m, it has a negative sign)
Let:
m - <span>the number of minutes the liquid is in the cooler.
a - the starting temperature
</span>a = 90<span>°F
</span>
<span>The temperature of a liquid must stay above 60°F:
f(m) > 60
Thus:
</span>f(m) = a - 3 * m
f(m) > 60
a - 3 * m > 60
90 - 3m > 60
90 - 60 > 3m
30 > 3 m
30/3 > m
10 > m
Or m < 10. So the correct answer is The liquid must be in the cooler fewer than 10 minutes.
Yes you are correct. You take half of the x coefficient 18 to get 9, then you square 9 to get 81
x^2+18x+81 is a perfect square trinomial which factors to (x+9)^2
