| blue book math answers
Page 490 #11:
Since “a” is negative, the parabola must open down. This eliminates E and D which open up. When x=0, y=c. So the graph must hit the y axis at (0, c). The question tells us that “c” is negative. Of the remaining choices only one graph hits the y axis at a negative value. The answer is A.
Page 490 #12:
Best way to attack this problem is to make up a location for Q inside the rectangle. Let us assume Q is 1 unit form BA and 3 units from CD. Then you should see that QP is 2 and QR is 6. So PR is 8 or B. It does not matter where you locate Q in the rectangle. You will still get the same answer.
Page 489 #8:
When the y coordinates are equal and lie on the circle, the x coordinates have to be an equal distance from the center. Of the choices only “C” gives x values which are an equal distance from the center. If you are having trouble seeing why this is true, try plotting all of the answers on the figure and you will be able to guesstimate the answer. | 
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