The answer is .55 I don't really know how to explain it but I hope this helps.
Find the slope
y-y1=m(x-x1)
F(x)=-2x+4
216/343
1/2 = square root
= 6/7 then cube = the answer
Find the greatest common factor between the numerator and denominator. The divide the numerator and denominator by the GCF.
It should be 84x 3636 euros