Answer: 229
To get this answer, we'll use the cosine ratio
cos(angle) = adjacent/hypotenuse
cos(A) = AC/AB
cos(35) = b/c
cos(35) = b/280
280*cos(35) = b
b = 280*cos(35)
b = 229.362572400918
b = 229
When you use your calculator, make sure it's in degree mode.