2.875 is 69/24 as a terminating decimal
The anser i got was 3.33333 but i think you would plot it as 3.25
(-2x + 4y)(3x - 7y) = -6x^2 - 28y^2 + 12yx
Given parameters:
Cost price of the article = Nu.28.30
Selling price of the article = Nu.29.30
Unknown:
Gain percentage = ?
The gain percentage is the same as the percentage profit on a trade.
The formula is given as:
Gain percentage = 
Profit = Selling price - Cost price
= Nu.29.30 - Nu.28.30
= Nu. 1
Now input the parameters and solve;
Gain percentage = 
= 3.5%
The gain percent is 3.5%