A reflection over the x-axis only change the signal of the coordinate y of the point. Hence, the coordinates of vertex B' are:

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20. 20+12=32. that's math(s).
-32+<u>50</u> =2(x^2+10x+25)
18=2(x+5)^2
9= (x+5)^2
+-<u /> <u>3</u> = x+5
x= -2 or x= <u>-8</u>
The two factors are 2 and p=10 so I used your equations and