Answer:
Option 1 , option 2 , option 4 are correct
Step-by-step explanation:
[tex]7x- 4z = \dfrac{9}{2y}\\\\\\7x = \dfrac{9}{2y}+4z\\\\\\7x = \dfrac{9}{2y}+ \dfrac{4z*2y}{1*2y}\\\\\\7x= \dfrac{9}{2y}+ \dfrac{8yz}{2y}\\\\\\7x= \dfrac{9+8yz}{2y}\\\\\\x= \dfrac{9+8yz}{14y}[/tex]
Option 1 is true
[tex]7x - 4z= \dfrac{9}{2y}\\\\\\7x= \dfrac{9}{2y}+4z\\\\\\7x- \dfrac{9}{2y}=4z\\\\\\ \dfrac{7x*2y}{1*2y}- \dfrac{9}{2y}=4z\\\\ \dfrac{14xy}{2y}- \dfrac{9}{2y}=4z\\\\\\ \dfrac{14xy-9}{2y}=4z\\\\\\ \dfrac{14xy-9}{2y*4}=z\\\\\\z= \dfrac{14xy-9}{8y}[/tex]
Option 2 is true
[tex]7x- 4z= \dfrac{9}{2y}\\\\\2y*(7x -4z)=9\\\\\\2y= \dfrac{9}{7x-4z}\\\\\\y= \dfrac{9}{2*(7x-4z)}\\\\\\y= \dfrac{9}{14x - 8z}[/tex]
Option 4 is true
