1.若a*a+b*b-6a+2b+10=0,则a+b的值是( )A.0B.2C.-2D.32.若a+b=3,则2a*a+4ab+2b*b-6的值为________

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1.若a*a+b*b-6a+2b+10=0,则a+b的值是( )A.0B.2C.-2D.32.若a+b=3,则2a*a+4ab+2b*b-6的值为________
1.若a*a+b*b-6a+2b+10=0,则a+b的值是( )
A.0
B.2
C.-2
D.3
2.若a+b=3,则2a*a+4ab+2b*b-6的值为________

1.若a*a+b*b-6a+2b+10=0,则a+b的值是( )A.0B.2C.-2D.32.若a+b=3,则2a*a+4ab+2b*b-6的值为________
1.若a*a+b*b-6a+2b+10=0,
则a²-6a+9+b²+2b+1=0
则(a-3)²+(b+1)²=0
则a-3=0,b+1=0
所以a=3,b=-1
所以a+b=2
所以选B
2.2a*a+4ab+2b*b-6=2(a²+2ab+b²)-6=2(a+b)²-6=2×3²-6=12