已知xy互为相反数,求式子3x-10+3y+Y分之5x y不等于0
问题描述:
已知xy互为相反数,求式子3x-10+3y+Y分之5x y不等于0
答
x、y互为相反数,则x+y=0 x=-y
于是
3x-10+3y+5x/y
=3(x+y)-10+5(-y)/y
=3*0-10-5
=-15