2a + b = 20
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What are the coordinates of the hole in the graph of the function f(x) ? f(x)=x2−9x−3 enter your answer in the boxes.

If eh = hg and hg=16, find the diameter of k

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.