a/b = 1-x/y 求b/a(a)x/(y-x)(b)y/x-1(c)y/(x-y)(d)x/y + 1(e)y/(y-x)第_数学解答

a/b = 1-x/y 求b/a
(a)x/(y-x)
(b)y/x-1
(c)y/(x-y)
(d)x/y + 1
(e)y/(y-x)
第2题
(3y-1)(2y+k) = ay的平方+by-5
求a+b等于多少

人气：470 ℃　时间：2020-02-05 19:10:06

解答

1.(e)
(3y-1)(2y+k) = ay^2+by-5
6y^2+(3k-2)y-k=ay^2+by-5
a=6,k=5 3k-2=b
a=6 b=13
a+b=19