tolong yang nomer 6 pake cara nya ya,.

X^2=(X-7)^2+(X-14)^2
X^2=X^2-14X+49+X^2-28X+196
X^2-42X+245=0
(X-35)(X-7)=0
X=35 or X=7
X=7 tdk mgk krn AC=X-7=7-7=0
jd X=35
AC=X-7=35-7=28cm