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64-16*d+112*d-28*d^2=64+32*d+4*d^2急.

题目详情
64-16*d+112*d-28*d^2=64+32*d+4*d^2 急.
▼优质解答
答案和解析
64-16*d+112*d-28*d^2=64+32*d+4*d^2
0=64-64+32*d+16*d-112*d+4*d^2+28*d^2
32d^2-64*d=0
d^2-2*d=0
d=0或者d=2