Y=13
(when you have fractions like the one in this problem, you get rid of them by multiplying both sides by the denominator.)
<h3>
Answer: 80.94 square cm</h3>
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Work Shown:
Area of parallelogram = base*height
Area of parallelogram = 11.4*7.1
Area of parallelogram = 80.94 square cm
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notes:
- The base and height always form a 90 degree angle (as shown by the small square marker).
- The side length of 8.9 cm is never used.
- We can write "square cm" as "cm^2" or

The answer to Q1 along with an explanation is shown in the picture;
Having a look at all the questions, they are all essentially the same type so can all be solved similarly;
So by following the method and explanation, you should be able to do the rest of the questions.
1+tan^2(y)=1/cos^2(y)
cos 2y -1=cos^2(y) -sin^2(y)-cos^2(y) -sin^2(y)