Question 156512
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The function y(x) is 
y=21-2x
And, they want to to solve for y for these values of x:
0,1,2,and 3
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x.|.y(x)....| y
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0 | 21-2(0) | 21
1 | 21- 2(1) | 19
2 | 21-2(2) | 17
3 | 21-2(3) | 15
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