Question

已知多项式(k-1)x^2-6xy-8y^2分解因式后为（mx+2y)(x-4y),求k,m的值、详细点,

Answer 1

打开（mx+2y)(x-4y)

=mx^2+(2-4m)xy-8y^2

=(k-1)x^2-6xy-8y^2

所以-6=2-4m

m=2

k-1=m=2

k=3