Question

1.若|x－5|＋ |y＋3|＝0,求2x＋3y的值

Answer 1

1.|x－5|＋ |y＋3|＝0则x=5,y=-3 ,则2x＋3y=1

2.c、d互为负倒数,则cd=1,a、b互为相反数,m分之a加b为0,则m大于0,又|m|＝2所以m=2

则－1＋m－cd=0