Find the length of the missing side
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It is a right angles triangle here.
So by using pythagoras theorem here;
unknown side length will be=[tex]\sqrt{18^2 -11^2 }[/tex]=[tex]\sqrt{324-121}[/tex]=[tex]\sqrt{203}[/tex] cm (Answer)
Use the Pythagorean theorem:
[tex]x^2+11^2=18^2\\\\x^2+121=324\ \ \ \ |-121\\\\x^2=203\to \boxed{x=\sqrt{203}\ m}[/tex]