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1. Sketch graph of y= - 2x^2 - 5x + 7 and label all axis intercepts and find the vertex

So I factorised and got - (2x+7)(x-1)

x=7/2
x=1

but when I look up the graph it appears it's supposed to be x = - 7/2

Am I supposed to ignore the minus in front of both brackets?
2. If you include the minus it'll still come out as -7/2.
-2x-7 =0
-2x=7
x=7/-2

2x+7=0
2x=-7
x=-7/2
3. You can't ignore the minus
5. (Original post by Edgemaster)
If you include the minus it'll still come out as -7/2.
-2x-7 =0
-2x=7
x=7/-2

2x+7=0
2x=-7
x=-7/2
And I am supposed to apply the minus to both brackets?
6. For finding where the graph intercepts the x-axis, you effectively are finding solutions to:

as y=0.

We can do this as we divide both sides of the equation by : -1 0 .

Therefore, the graph croses the x-axis at x = -7/2 and x=1.

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