已知a²-ab=15,ab-b²=-10,则代数式a²-b²=_______.
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![已知a²-ab=15,ab-b²=-10,则代数式a²-b²=_______.](/uploads/image/z/8762355-27-5.jpg?t=%E5%B7%B2%E7%9F%A5a%26%23178%3B-ab%3D15%2Cab-b%26%23178%3B%3D-10%2C%E5%88%99%E4%BB%A3%E6%95%B0%E5%BC%8Fa%26%23178%3B-b%26%23178%3B%3D_______.)
已知a²-ab=15,ab-b²=-10,则代数式a²-b²=_______.
已知a²-ab=15,ab-b²=-10,则代数式a²-b²=_______.
已知a²-ab=15,ab-b²=-10,则代数式a²-b²=_______.
5
由题意可知a2-ab+(ab-b2)=a2-b2=15+(-10)=5.
a²-b²=(a²-ab)+(ab-b²)=15+(-10)=5