Help plz! I dont understand this problem? Abi has 20 cents. She bought x pencils for 3 cents each. If y is equal to the number of cents left, write an equation that shows the dependence of y on x. What is the domain of the function?

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Ammonia molecules have three hydrogen atoms and one nitrogen atom.how many of each atom arein five molecules of ammonia

The art class is planning to paint a mural on an outside wall. this figure is a scale drawing of the wall. width: 11 in length: 28 in unit rate: 1.5 ft per in. write the ratio of the area of the drawing to the area of the actual mural. write your answer as a unit rate. show that this unit rate is equal to the square of the unit rate 1.5 ft per in

Find the zeros of each function. f(x) = 6x^2 - 7x - 20