Math III Section 4.6 #29 and #31

N. Edwards

The Positives?

No this problem does not show any positive sign switches and/or changes. Since all the signs are positive there isn't any switches making the positive switches 0.

The Negative

There are 3 different jumps between the signs of negative to positives. Since you are suppose to subtract 2 from the amount of jumps, that leaves 3 and 1 as possible negative real roots.

The Conclusion

He was correct with the positive answers but with the negatives he wasn't correct. He only changed the first sign and kept the other signs the same making it wrong. He came up with only one answer choice when it was really two different ones. He didn't correctly change the x's giving him only 1 as an answer. If he would have used parentheses he probably would have had an easy time noticing that he didn't put all the signs in to get it correct.

Since the shorter base of the trapezoid is twice the height and the longer base is 4 feet longer than the shorter base this is how you would draw your work.

Here is a Brace Map example if the height was equal to four of how the answers could be.

While the trapezoid formula is A=(1/2)(h)(b1 + b2) we will have to replace the variables with actual numbers since the question stated she wanted 60^2 garden that will be in place of "A" and the rest of the problem we can solve so far will be in the way it is above.

Now the next part we have is to find out what the height "H" is equal to,to help us find our bases. Since you have already filled in your variables with numbers its time to combine like terms and solve.

When you divide 34 by 4 you will get 8.5. 8.5 rounds to 9 so to find the square root of 9 it will be 4.5 which rounds to 5. Therefore, making 5 your height now it time to put it into the question/formula and check your answer.

Once you check your answer it shows that it is correct. Making 5 the correct answer for the height and the bases are equal to 10 and 14. The shortest base is 10 and the longest is 14.