Thanks Plato that was a massive help! I knew nothing about hyperbola so I went on to read a bit more after looking at your reply and came up with this which I hope is correct!

(cosh^2(x)-sinh^2(x)0+5sinh(x)=1-6

Using identity (cosh^2(x)-sinh^2(x))=1

1+5 sinh(x) = -5

5sinh(x) = -5-1

5 sinh(x) = -6

sinh(x)=-6/5

sinh(x)=-1.2

sinh^-1(-1.2)=x

x = -1.015973134