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2. In the XY plane, at what two points does the graph of y= (x+a)(x+b) intersect the X axis?
1) a + b = 1
2) the graph intersects Y axis at (0, -6)
answer.- y=x^2+x(a+b)+ab
graph intersects x-axis when y=0
therefore,x^2+x(a+b)+ab=0
=>x^2+x-6=0 (from 1 & 2)
therefore, x=-3,2
answer-C
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