题目

 阅读理解。     Australia has a lot of lovely animals. You cannot find them anywhere else in the world. The most famous ones are kangaroos and koalas(树袋熊).  The kangaroo is the symbol of Australia. They have large eyes and ears. They don’t walk, they jump. They use their strong back legs. They can jump at up to 74 kilometers per hour. They can go over nine meters in one jump!  Kangaroo mothers have pouches(育儿袋) to carry their babies. The babies stay inside to get milk and keep warm.  Kangaroos are everywhere in Australia. They are on TV, in books and in the shops.已知二次函数y=-x2+6x-5的图象与x轴相交于A、B两点，与y轴相交于C，求△ABC面积．