I'm brain feels squishy.
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Answer:
x = 9 (it is seriously not drawn to scale)
Step-by-step explanation:
BC = DC^2 + BD^2 (Pythagorean theorem)
BC = 4^2 + 6^2
BC = 16 + 36
BC = 52^2
BC = 2sqrt13
BC/AB = DC/BD
(2sqrt13)/AB = 4/6
6(2sqrt13) = 4(AB)
12sqrt13 = 4AB
3sqrt13 = AB
AC^2 = AB^2 + BC^2 (Pythagorean Theorem)
AC^2 = (3sqrt13)^2 + (2sqrt13)^2
AC^2 = 117 + 52
AC^2 = 169
AC = 13
AD + DC = AC
AD + 4= 13
AD = 9