exam Maths Puzzle Numerical Ability

I am confused. o.k. the problem is xsquared+7x+9=0 i do not get how to find the vertex . i know it has to do with the it being max or miminmum . right ?
Thanks for the help !!
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exam Other Question

Please help me.

I have simplified the equation: 2/5-y/y-2. I got -3y+4/5(y-2). Is it correct? Can it be further simplified?

Thanks
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