Me find x using pythagorean theorem

Can someone me find the original price? the discount is 5% and the sale price is $68.40

Jane is cooking beans and rice for dinner tonight. she has 4 cans of black beans, 6 cans of red beans, and 3 cans of garbanzo beans in her cupboard. if she grabs a can of beans without looking at the label, what is the probability of her making black beans and rice for dinner?

If f(x)=x^2- 4 and g(x)=x^2 plus 2 x, (c) (f-/3) = ? (simplify your answer.)