Since 5 is in the hundreds place, the value of the 5 is 500.
I'm assuming you want us to solve for the unknown variable z

Combine like terms on the right side

Use the distributive property on the left side

Add both sides by 20 to cancel out the "-20" on the left side

Divide both sides by 10

That is the value of the known variable, z, in this equation. Let me know if you need any clarifications, thanks!
~ Padoru
Answer:
y = -3x +9
Step-by-step explanation: