There is no common factor between 15, 17 and 18 because 17 is prime.
15z² +17z - 18 =
d = 17² - 4.15.-18
d = 289 + 1080
d = 1369
z = (-17 +/- \/1369) : 2 * 15
z = (-17 + 37) : 30
z' = 20 : 30 = 2/3
z" = (-17 - 37) : 30
z" = -54 : 30 = -1.8
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Scatter Plot<span>. ... A </span>graph<span> of plotted points that show the relationship between two sets of data. In this example, each dot represents one person's weight versus their height</span>
D = 171 - (61+53) = 171 -124 = 47
E = 171 - 90 = 81
A = 81 - (34+24) = 81 - 58 = 23
B = 61 - 23 = 38
C = 90 - (33+ 38) = 90 - 71 = 19
answer is B.