The enthalpy of a reaction can be measured using a Calorimeter
2x^2 - 11 = 87
2x^2 = 87 + 11 = 98
x^2 = 98/2 = 49
x = sqrt (49) = + or - 7
Answer is (1) 160 km in 2 hours and
(2) 16 miles in 12 minutes.
Step by step.
80 km / 1 hour = x km /2 hours
Cross multiply =
x = 160
The second one requires a little more math. Because we are looking at how far in minutes, we change the rate of 80km in 1 hour to 80 km in 60 minutes.
80 km / 60 = x / 12
Cross multiply
12x = 960
Solve for x by dividing both sides by 12
X = 16
I did the math on a print screen to explain the cross multiply.
<u><em>FALSE.</em></u><em></em>
A composite number is the opposite of a prime number. This is false because of the possibility of the following scenario:
The two numbers are 1 and a prime number.
This is because <em>one multiplied by any number is that number.</em> A prime number cannot become a composite number just because it is being multiplied by one. For example:
1 x 7 = 7 (prime)
Hope this helps!
~<em>Archimedes El</em>∈<em>ven</em>