please someone useful help me it's always people who answer who say they don't know the answer
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Answer:
Step-by-step explanation:
the equation is 3-8*cos(x) = 7
plugging in 45° to Cos give [tex]\sqrt{2}[/tex] / 2
then the equations looks like
3-8* ([tex]\sqrt{2}[/tex] / 2) = y
3-4[tex]\sqrt{2}[/tex] = y
there is your answer... don't get rid of the square root.. that's an exact answer