Find the sale price of each item. Round to two decimal places when necessary. Original Price: $22.50

Markup: 42%

Which of the functions below could have created this graph?

Parabolas y=−2x^2 and y=2x^2+k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.

Idon't get undoing if its pass adding and subtracting so can someone ? x-2 over 5 = 18