Plotting a graph of a square root function does not show the expected graph

Question

New to Mathematica and have been given some assignments for practice.
I am currently trying to plot the following function:
$$|sqrt{x-1}+5|$$
This is how other sites show what this graph should look like:

But trying to plot the same function in Mathematica gives the following unexpected graph:

That straight line coming in from the left shouldn't be there, and no matter how I try to re-organize the plot function it seems to stay.
Am I misunderstanding something? Am I using the Plot function wrong? Thanks for any help and apologies if this is a noob question!

cvgmt · Accepted Answer

Use RealAbs instead of Abs  since Abs is a Complex function.
And the Sqrt is also a Complex function, sometimes we use Surd instead of Sqrt or Power
if we assume x is a real numbers,we can use ComplexExpand to observe the expression of Abs[Sqrt[x - 1] + 5]
Abs[Sqrt[x - 1] + 5] // ComplexExpand

(*  Sqrt[(5 + ((-1 + x)^2)^(1/4) Cos[1/2 Arg[-1 + x]])^2 + 
 Sqrt[(-1 + x)^2] Sin[1/2 Arg[-1 + x]]^2] *)

So we had to use another way.
Plot[RealAbs[Surd[x-1,2]+5],{x,-5,5},AxesOrigin -> {0, 0}]

Plotting a graph of a square root function does not show the expected graph

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