Ms. Cindy's ACT Math Book

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Errata:

In the example on page 184:  The problem and the solution don't match.  The problem asks for the minimum value of y if y = x^2 + 4x - 10, but the solution is given for y = x^2 + 3x - 10.  The easiest thing to do would be to change the "4" given in the problem to a "3".  If you have already worked the problem with a 4 in it, and you would like to know if your answer is correct, the answer should be -14.  The original quadratic doesn't factor, so you would have to put it in vertex form, graph it, or find the roots with the quadratic equation and average them.  No matter which method you choose, the vertex will be at (-2, -14).

In the example on page 236:  The problem and the solution don't match.  The problem says that the interest is compounded daily, but the solution is for interest compounded annually.  The easiest thing to do would be to change the phrase "compounded daily" to "compounded annually", but if you have already answered the original question and you would like to check your work, the answer would be $10,570.68.  To get there, you would divide 15,000 by (1 + .07/365) raised to the power of 5*365.

In the example on page 204, the problem statement is missing the exponent.  The expression in parentheses should be squared. (The exponent is present in the solution.)  I've put out a BOLO for the missing exponent, but until it turns up, you'll have to write it in yourself.