Answer:
8² = 4² + 5² - 2(4)(5) cos(P)
which is the third option
Explanation:
The general rule of cosine is:
a² = b² + c² - 2bc*cos(A)
In our triangle:
a is substituted by p = 8 cm
b is substituted by n = 4 cm
c is substituted by m = 5 cm
A is substituted by P which we want to find
Replace the variables in the general equation with the givens as follows:
p² = n² + m² - 2mn*cos(P)
8² = 4² + 5² - 2(4)(5) cos(P)
Hope this helps :)
$7.50 per hour times <span>32.5 hours equals $243.75
$ 7.50 per hour
x 32.5 worked hours
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$243.75 is her check</span>
The hydronium ion is H₃O⁺ and its concentration is equivalent to the H⁺ ion concentration. The H⁺ ion concentration is given by:
pH = -log[H⁺]
[H⁺] = 10^(-8.2)
[H⁺] = 6.31 x 10⁻⁹ mole/dm³
The hydronium ion concentration is 6.31 x 10⁻⁹ mole/dm³
