You can solve for sides of a triangle using the following equation.
A = arccos (b^2 + c^2 - a^2/2bc)
And likewise for other variables by moving the letters.
Ultimately, in this problem you get the following angle measures:
15.87
23.97
140.16
Answer:
Step-by-step explanation:
a = 2, b = 1, c = -3
We need to factor this by finding the product of a and c, then from there find which factors of a * c will either add or subtract to give us b.
a * c = 6 and the factors of 6 and 1 and 6, 2 and 3. Well, 6 - 1 doesn't equal 1 and neither does 6 + 1. So our factors are 3 and 2. In order to combine those to get a 1 (our b), we will subtract 2 from 3 since 3 - 2 = 1. That means that 3 is positive and 2 is negative. Filling in the formula with 3 and 2 in place of 1 looks like this (always remember to put the absolute value of the largest number first):

Group the first 2 terms together and the second 2 term together in order to factor:
and factor out what's common in each set of parenthesis.

Notice that when we factor out a -1 from the second set of parenthesis, we can distribute it back in to get the equation we started with. We know that factoring by grouping "works" if what is inside both sets of parenthesis is exactly the same. Ours are identical: (2x + 3). That is common now, and can be factored out:

That matches your first choice
Translating the words into formula, we have

In fact, we have that the pay rate is the total payment divided by the number of hours worked.
We can solve this formula for w in two steps: starting from the formula above, multiply both sides by w:

And then divide both sides by r:
