Answer:
80%
Step-by-step explanation:
80%
Hope this helps!
plx give brainliest
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:
answer is .A
Step-by-step explanation:
Answer:
The remaining solutions are -7 and 3.
Step-by-step explanation:
The synthetic division is shown in the attachment. After dividing the first two found factors from the polynomial, the remaining quadratic is ...
x^2 +4x -21 = 0
Its rational roots will be factors of -21, and the sum of their opposites will be 4. Knowing that 21 = 3·7, we can guess that the remaining roots are -7 and 3. The synthetic division confirms that. (A graph also confirms it.)
So a triangle angles must add up to 180. You would subtract 180 by the two known angle which are 90 and 30. Then if you subtract them you would get 60. The final answer is 60