I think you should combine like terms
Answer:
it would be A:55%
Step-by-step explanation
For percent, to make it easier try to turn it into a 100.
20x5=100
do the same to the 9.
9x5=45.
Now subtract 45 from 100.
100-45=55.
There was a discount of 55%.
Answer: CasioFX-CG50
Step-by-step explanation: you can get it on amazon
