Khaled invested a certain amount of money in a bank. The bank paid him AED 9000 after a given period of time. If the interest paid by the bank was AED 1200, calculate the amount of money Khaled invested?

ranks (& how to earn them):

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how to award brainliest:

you must wait until 2 people answer to award brainliest. i'm pretty sure that it should be next to the "" and "comments" buttons.  

hint: which coefficient is a multiple of 360°?

step-by-step explanation:

since no one answered yet i will give it a shot, not completely sure tho.

i think it should be y=cos(x+2pi), (third answer, answer c)

good luck.