【简答题】Dolores Huerta has worked hard most of her life to help other people. She has helped change things so that farm workers can have a better life. Dolores grew up in California. She was a good student an...
【简答题】已知关于x的方程x 2 -7x+k=0(*). (1)请你选择一个合适的整数k,使得到的方程有两个不相等的实数根,并说明它的正确性. (2)如果方程(*)的两个实数根x 1 ,x 2 的值恰好是一个菱形的两条对角线长且满足 x 1 2 x 2 2 - x 1 2 - x 2 2 -2 x 1 x 2 =95,求该菱形的面积.