Answer:
y = 
Step-by-step explanation:
Given
Ry - wy = t ← factor out y from each term on the left side
y(R - w) = t ( divide both sides by (R - w ) )
y = 
300,000 + 80,000+2,000+700+0+6 , is your answer.
a function can't have one input mapped to multiple outputs. this is the case for where 4 maps to -2 and 2, so remove (4, -2)