Answer:
The washing machine cost $600 before tax
Explanation:
Percentages
The washing machine cost $651 including a tax of 8.5%.
If x was the cost of the washing machine before tax, then the tax was:
x*8.5/100 = 0.085x
It was added to the original price:
x + 0.085x = 1.085x
That is the final price, thus
1.085x=$651
Solving:
x = $651/1.085
x = $600
The washing machine cost $600 before tax