已知m，x，y满足条件：（1）23（x-5）2+5|m|=0；（2）-2a2by+1与3a2b3是同类项．求代数式0.375x2y+5m2x-{-716x2y}+[-14xy2+（-316x2y-3.475xy2）-6.275xy2]．

Question

已知m，x，y满足条件：（1）(2)/(3)（x-5）²+5|m|=0；（2）-2a²b^y+1与3a²b³是同类项．求代数式0.375x²y+5m²x-{-(7)/(16)x²y}+[-(1)/(4)xy²+（-(3)/(16)x²y-3.475xy²）-6.275xy²]．

Answer 1

因为（x-5）²，|m|都是非负数，
所以由（1）可得：x=5，m=0，
由（2）得y+1=3，所以y=2．
下面先化简所求代数式，然后再代入求值．
0.375x²y+5m²x-{-(7)/(16)x²y+[-(1)/(4)xy²+（-(3)/(16)x²y-3.475xy²）-6.275xy²]}
=0.375x²y+5m²x+(7)/(16)x²y+(1)/(4)xy²+(3)/(16)x²y+3.475xy²+6.275xy²
=x²y+5m²x+10xy²
=5²×2+0+10×5×2²
=250．