如果|3a-b+5|+(5a-7b+3)²=0,那么求a、b的值?
问题描述:
如果|3a-b+5|+(5a-7b+3)²=0,那么求a、b的值?
答
因为,|3a-b+5| ≥ 0 ,(5a-7b+3)2 ≥ 0 ,所以,|3a-b+5|+(5a-7b+3)2 ≥ 0 ;要使 |3a-b+5|+(5a-7b+3)2 = 0 ,必须 |3a-b+5| = 0 ,(5a-7b+3)2 = 0 ;则有:3a-b+5 = 0 ,5a-7b+3 = 0 ;解得:a = -2 ,b = -1 ....