10分!容易數學題!!!

-8(2x+1)(2x+1)=-64
(-16x-8)(2x+1)=-64
-32x^2-16x-16x-8=-64
-32x^2 -32x+56=0
4x^2 + 4x -7 =0
[-4 正負開方4^2 -4(4)(-7)]over [2(4)]
-4正負開方128 over 8
-1正負開方8over2

As follow AS~~~

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