Need help with maths HW

I need help with my maths homework that is due tomorrow!!!Sorry for gram mistakes I am rushing and I really dont need an all nighter !!

Look at this triangle


Triangle image here: https://notepad.pw/yso11vdh

Show working to explain why angle X must be a right angle.
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Help would be appreciated very much and please explain so I dont forget and get to do it myself...!!

Thanks Very much!!!!

[EDIT] 1 Min in..HELP!!!!

[EDIT] Got it myself! Well that concludes my brief foray into forums! no one replys!!!