For this case we have the following quadratic equation:
The solutions are given by:
We have to:
Substituting:
Answer:
Answer:$68.17
Step-by-step explanation:52.60 times 1.08= 56.81
56.81 times 1.20=68.17
It would be (-5, 15) or b.
Answer: 90,000
Step-by-step explanation:
10,000 x 45 = 450,000
20% of 450,000 is 90,000
From the double-angle identity,
we can rewritte our given equation as:
By factoring 2cosx on the left hand side, we have
This equation has 2 solutions when
From equation (A), we obtain
and from equation (B), we have
On the other hand, we can find one more solution from the original equation by substituting x=0, that is,
then, x=0 is another solution. In summary, we have obtained the following solutions:
However, the intersection of the last set is empty. So the unique solution is x=0 as we can corroborate on the following picture:
Therefore, the solution set is: {0}