Question

已知代数式7x(x+5)与代数式-6x^2-37x-9的值互为相反数,则x=

Answer 1

值互为相反数则相加为0

7x(x+5)+(-6x²-37x-9)=0

7x²+35x-6x²-37x-9=0

x²-2x=9

x²-2x+1=9+1

(x-1)²=10

x-1=±√10

x=1-√10,x=1+√10