Answer:
30
Step-by-step explanation:
You’re correct
Answer:
0.6 °C/min
Step-by-step explanation:
The relationship between rates and movement is ...
time = distance/speed
Here, the "distance" is measured in °C, and the "speed" is the rate of change of temperature.
For the first half of the heating, the time required is ...
(50°C -0°C)/(1.5 °C/min) = 50/(3/2) min = 100/3 min
For the second half of the heating, the time required is ...
(100°C -50°C)/(4/10 °C/min) = 50/(4/10) = 125 min
Then the total time is ...
((100/3) +125) min = (475/3) min
And the average rate of temperature increase is ...
total temperature change / total time
= (100°C -0°C)/(475/3 min) = 300/475 °C/min = 12/19 °C/min ≈ 0.6 °C/min
Answer:
-4 ± 2√6
Step-by-step explanation:
Rewritten in standard quadratic form, x^2+8x-2=18 becomes x^2 + 8x - 20 = 0.
Here the quadratic coefficients are a = 1, b = 8 and c = -20 and so the discriminant is b^2 - 4ac, or 8^2 - 4(1)(-20), or 96.
Because the discriminant is positive, we know that this quadratic has two different real roots. These roots are:
-b ± √(b² - 4ac)
x = -------------------------
2a
which in this case comes out to:
-8 ± √96 -8 ± 4√6
x = ------------------ = ------------------- = -4 ± 2√6
2 2