<span>This question, in my opinion, is not well stated. If f(x) = √x, as the question statement seems to say, then the domain is not x<7. Rather, the domain is x≥0.
If f(x) is not the square root function, but say f(x) = √(7-x) then the domain is x≤7, and for this function then the appropriate answer is d), since the x-term inside the radical has a negative coefficient.</span>
![\begin{tabular} {|c|c|} Statement&Reason\\[1ex] \overline{WX}\cong\overline{XY},\ \overline{XZ}\ bisects\ \angle WXY&Given\\ \angle WXY\cong\angle YXZ & Deifinition of an angle bisector\\ \overline{XZ}\cong\overline{ZX}&Refrexive Property of \cong\\ \triangle WXZ\cong\triangle YXZ&SAS \end{tabular}](https://tex.z-dn.net/?f=%5Cbegin%7Btabular%7D%0A%7B%7Cc%7Cc%7C%7D%0AStatement%26Reason%5C%5C%5B1ex%5D%0A%5Coverline%7BWX%7D%5Ccong%5Coverline%7BXY%7D%2C%5C%20%5Coverline%7BXZ%7D%5C%20bisects%5C%20%5Cangle%20WXY%26Given%5C%5C%0A%5Cangle%20WXY%5Ccong%5Cangle%20YXZ%20%26%20Deifinition%20of%20an%20angle%20bisector%5C%5C%0A%5Coverline%7BXZ%7D%5Ccong%5Coverline%7BZX%7D%26Refrexive%20Property%20of%20%5Ccong%5C%5C%0A%5Ctriangle%20WXZ%5Ccong%5Ctriangle%20YXZ%26SAS%0A%5Cend%7Btabular%7D)
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