已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数式:(2x²-3xy+6y²)-m(3x²-xy=9y²)的值.
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![已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数式:(2x²-3xy+6y²)-m(3x²-xy=9y²)的值.](/uploads/image/z/6913628-44-8.jpg?t=%E5%B7%B2%E7%9F%A5m%2Cx%2Cy%E6%BB%A1%E8%B6%B3%EF%BC%9A%EF%BC%881%EF%BC%89%EF%BC%88x-5%EF%BC%89%26sup2%3B%2B%7Cm%7C%EF%BC%9D0%2C%EF%BC%882%EF%BC%89-2ab%EF%BC%88y%E5%B9%B3%E6%96%B9%EF%BC%89%E4%B8%8E4ab%EF%BC%883%E6%AC%A1%E6%96%B9%EF%BC%89%E6%98%AF%E5%90%8C%E7%B1%BB%E9%A1%B9.%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%EF%BC%9A%EF%BC%882x%26sup2%3B-3xy%2B6y%26sup2%3B%EF%BC%89-m%283x%26sup2%3B-xy%3D9y%26sup2%3B%EF%BC%89%E7%9A%84%E5%80%BC.)
已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数式:(2x²-3xy+6y²)-m(3x²-xy=9y²)的值.
已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数式:(2x²-3xy+6y²)-m(3x²-xy=9y²)的值.
已知m,x,y满足:(1)(x-5)²+|m|=0,(2)-2ab(y平方)与4ab(3次方)是同类项.求代数式:(2x²-3xy+6y²)-m(3x²-xy=9y²)的值.
2/3(x-5)^2+5*(m的绝对值)
是不是2/3(x-5)^2+5*(m的绝对值)=0?
如果是则(x-5)^2>=0,所以2/3(x-5)^2>=0
|m|〉=0,所以5*|m|>=0
两个大于等于0的数相加等于0,若有一个大于0,则另一个小于0,不成立
所以两个都等于0
所以x-5=0,m=0
x=5
-2a^2b^(y+1)与3a^2b^3是同类项
所以a和b的指数对应相等
所以y+1=3,y=2
0.375x^2y+5m^2x-{-7/16x^2y+[-1/4xy^2+(-3/16x^2y-3.475xy^2)]-6.275xy^2}
=0.375x^2y+5*0^(2*5)-[-7/16x^2y+(-1/4xy^2-3/16x^2y-3.475xy^2)-6.275xy^2]
=0.375x^2y+0-(-7/16x^2y-1/4xy^2-3/16x^2y-3.475xy^2-6.275xy^2)
=0.375x^2y-(-5/8x^2y-10xy^2)
=0.375x^2y+5/8x^2y+10xy^2
=x^2y+10xy^2
=5^2*2+10*5*2^2
=50+200
=250
(1)由0+0=0,得:(x-5)平方=0.所以x=5.m的绝对值=0.m=0
(2)没看懂.+我好友说清楚