Question

Tìm số nguyên x , biết

a , 15x = -75

b , 3 IxI = 18

Answer 1

a, 15x=-75

= -75:15

=-5

b,3.\(\left|x\right|\)=18

\(\left|x\right|\)     =18:3

TH1:

x=-6

TH2:

x=6

Answer 2

a)15x=-75                                                   b)3|x|=18

->x   =-75:15                                                 |x|  =18:3

->x   =-5                                                        |x| =6

                                                                    XE{6;-6}

Answer 3

a. 15x = -75

 x = -75 : 15

x = -5

b. 3 |x| = 18

|x| = 18 : 3 hoặc |x| = -18 : 3

|x| = 6 hoặc |x| = -6

=> x = 6