Solve For Z
A. 12
B.
[tex]4 \sqrt{7} [/tex]
C.
[tex]3 \sqrt{7} [/tex]
D. 51
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Triangle ABC and triangle BCD are similar, therefore the sides are in proportion:
[tex]\dfrac{z}{9+7}=\dfrac{7}{z}[/tex]
cross multiply
[tex]z^2=16\cdot7\to z=\sqrt{16\cdot7}\\\\z=\sqrt{16}\cdot\sqrt7\\\\z=4\sqrt7[/tex]
Answer: B. 4√7