What are the coordinates of the x-intercepts of the graph of y = 2x2 + 6x – 20?

(–5, 0), (2, 0)
(5, 0), (–2, 0)
(–4, 0), (10, 0)
(4, 0), (–10, 0)

Question

What are the coordinates of the x-intercepts of the graph of y = 2x2 + 6x – 20? 

(–5, 0), (2, 0)
(5, 0), (–2, 0)
(–4, 0), (10, 0)
(4, 0), (–10, 0)

anonymous · Answer

For the x-intercepts y will be zero right?
All you have to do is plug in y=0 for 
y = 2x2 + 6x – 20
and solve for x

0= 2x2 + 6x – 20

You might need to use the quadratic formula to solve for x.

anonymous · Answer

After you find your two x : x1 and x2 you pair it with y=0

(x1,0)  &  (x2,0)

anonymous · Answer

You think you can solve it with the information I gave you?

anonymous · Answer

check factoring first...
2x^2 + 6x -20
= 2 ( x^2 + 3x - 10)
= 2 (x+5) (x -2)

anonymous · Answer

is it the second one?

anonymous · Answer

no, it's the first one... be careful... because one factor is (x+5), x has to be -5 so that (x+5) will be = 0.  same with the other factor...

anonymous · Answer

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