We have 112.5 = 225/2; cos112.5 < 0 because 90 < 112.5 < 180;
cos 112.5 = cos(225/2);
We use the trigonometric formula: cos(x/2) = -

;
Then, cos(225/2) = -

;
We have the formula: cos(270 - x) = -sinx (because cos(a-b) = cosacosb + sinasinb);
Then, cos225 = cos(270-45) = -sin45 = -

Finally, cos112.5 = -
Answer:
85% of the job is finished.
Step-by-step explanation:
The way to find the percentage is to divide 119 by 140, which will come out to be .85.
Multiply .85 by 10 to have it as a whole number for the percentage.
Answer:
A
Step-by-step explanation:
Alright well for (A) you will round $5280 to $5300. Then you multiply $5300 by 28.
For (B) you just round up. So again $5280 rounds up to $5300.
No, as if you reduce 4/16 it is 1/4, not 3/5, therefore they are not equivalent.