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 the y axis at (0,-6)
OA is C
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Graphs point of intersectoin
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camitava
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Gmatrant, as the line crosses the X-axis, so y = 0 and (x + a)(y + b) = 0
So x = -a and -b :- These are the points thru which that equ has passed thru X-axis. But we have to calculate the value of a and b. And that can be done by statement - 2. As, -6 = (0 + a)(0 + b) or ab = -6
And by statement - 1, a + b = -1
From these two questions, we can easily solve the values of a and b. So IMO C.
So x = -a and -b :- These are the points thru which that equ has passed thru X-axis. But we have to calculate the value of a and b. And that can be done by statement - 2. As, -6 = (0 + a)(0 + b) or ab = -6
And by statement - 1, a + b = -1
From these two questions, we can easily solve the values of a and b. So IMO C.
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
