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Hey!
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The opposite of -10 is 10.
Number line in image below.
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Hope This Helped! Good Luck!
Answer:
16.2
Step-by-step explanation:
Tan(angle)=opposite/ adjacent
Angle= 45
Opposite side= x
Adjacent side =10
Substitute into equation: tan(45) = x/ 10
Rearrange (multiply each side by 10): 10 x tan(45) = x
Then work it out on calculator
Area is defined as a product of sides when we talk about squares.

The area of the front cover of notebook is 400 centimetres squared.
Hope this helps.
r3t40