Will only name Brainliest if its the correct answer!
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Answer:
2
Step-by-step explanation:
[tex] \frac{( {( {x}^{3} {x}^{4} )}^{2}) }{ {( {x}^{5} {x}^{3} )}^{z} } = {x}^{ - 2} \\ \\ \frac{( {( {x}^{3 + 4} )}^{2}) }{ {( {x}^{5 + 3} )}^{z} } = {x}^{ - 2} \\ \\ \frac{ {(( {x}^{7} ) }^{2}) }{ {( {x}^{8} )}^{z} } = {x}^{ - 2} \\ \\ \frac{ {x}^{7 \times 2} }{ {x}^{8 \times z} } = {x}^{ - 2} \\ \\ \frac{ {x}^{14} }{ {x}^{8z} } = {x}^{ - 2} \\ \\ {x}^{14 - 8z} = {x}^{ - 2} \\ \\ 14 - 8z = - 2 \\ \\ 14 + 2 = 8z \\ \\ 16 = 8z \\ \\ z = \frac{16}{8} \\ \\ z = 2[/tex]