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Question

ilovepuppieslol · Answer

@Jamierox4ev3r

ilovepuppieslol · Answer

@mathmale

mathmale · Answer

Hello!!
I haven't studied or practiced this type of question for a while, but believe I can help you anyway.

If and only if lines s and t are parallel, which they appear to be, then the angle that line t makes with line d is 90 degrees, just as the angle that line s makes with line d is 90 degrees.   If the former is 90 degrees, that immediately implies that lines t and d are perpendicular.

ilovepuppieslol · Answer

would that be the Perpendicular Transversal Theroem? @mathmale

mathmale · Answer

To be bluntly honest, I don't know.  To answer this question, I would have to look up all four of the possible answer choices, which I urge you to do.  It's possible that one or more of these fancy-sounding theorems are nothing but hot air ... inventions!

ilovepuppieslol · Answer

i see, thank you warren :) @mathmale

mathmale · Answer

;)

directrix · Answer

@ILovePuppiesLol 

The theorem that comes to mind is this:

In a plane, if a line is perpendicular to one of two parallel lines, then it is perpendicular to the other one also.

I think you are correct in marking the Perpendicular Transversal Theorem.