作业帮已知|x-2|与[y-(1/3)x]²互为相反数,化简并求代数式的值2x²+(-x²+3xy+2y²)-(x²-xy+2y²)
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![已知|x-2|与[y-(1/3)x]²互为相反数,化简并求代数式的值2x²+(-x²+3xy+2y²)-(x²-xy+2y²)](/uploads/image/z/6987259-19-9.jpg?t=%E5%B7%B2%E7%9F%A5%7Cx-2%7C%E4%B8%8E%5By-%281%2F3%29x%5D%26%23178%3B%E4%BA%92%E4%B8%BA%E7%9B%B8%E5%8F%8D%E6%95%B0%2C%E5%8C%96%E7%AE%80%E5%B9%B6%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%E7%9A%84%E5%80%BC2x%26%23178%3B%2B%28-x%26%23178%3B%2B3xy%2B2y%26%23178%3B%29-%28x%26%23178%3B-xy%2B2y%26%23178%3B%29)
已知|x-2|与[y-(1/3)x]²互为相反数,化简并求代数式的值2x²+(-x²+3xy+2y²)-(x²-xy+2y²)
已知|x-2|与[y-(1/3)x]²互为相反数,化简并求代数式的值2x²+(-x²+3xy+2y²)-(x²-xy+2y²)
已知|x-2|与[y-(1/3)x]²互为相反数,化简并求代数式的值2x²+(-x²+3xy+2y²)-(x²-xy+2y²)
2x²+(-x²+3xy+2y²)-(x²-xy+2y²)=2x²-x²+3xy+2y²-x²+xy-2y²=4xy
因为|x-2|与[y-(1/3)x]²互为相反数,所以|x-2|=0,既x=2;[y-(1/3)x]²=0,既y=2/3
则4xy=4*2*2/3=16/3