Question

tìm x biết :                                                                                                                                                                                                           a) 456 + (x - 357) = 1362;       b) (2345 - x) - 183 = 2014;         c) (x - 2005) .2006 = 0;              d) 480 + 45. 4 = (x + 125) :5 + 260;                e) 2005. (x - 2006) = 2005;        g) [(x + 50). 50 - 50] : 50= 50  

Answer 1

a) 456 + (x - 357) = 1362

=>x - 357 = 1362 - 456

=>x - 357 = 906

=>x = 906 + 357

=>x = 1263

b)(2345 - x) - 183 = 2014

=>2345 - x = 2014 + 183

=> 2345 - x = 2197

=> x = 2345 - 2197 = 148

c)(x-2005).2006=0

=>x-2005=0

=>x=2005

d)480+45.4=(x+125):5+60

=>480+180=x:5+125:5+60

=>660=x:5+25+60

=>660=x:5+85

=>x:5=660-85=575

=>x=575.5=2875

e)2005.(x-2006)=2005

=>x-2006=1

=>x=2--7

g)[(x+50).50-50]:50=50

=>(x+50).50-50=1

=>(x+50).50=51

=>x+50=51.50=2550

=>x=2550-50

=>x=2500

Answer 2

a) 456 + (x - 357) = 1362

=>x - 357 = 1362 - 456

=>x - 357 = 906

=>x = 906 + 357

=>x = 1263

b)(2345 - x) - 183 = 2014

=>2345 - x = 2014 + 183

=> 2345 - x = 2197

=> x = 2345 - 2197 = 148

c)(x-2005).2006=0

=>x-2005=0

=>x=2005

d)480+45.4=(x+125):5+60

=>480+180=x:5+125:5+60

=>660=x:5+25+60

=>660=x:5+85

=>x:5=660-85=575

=>x=575.5=2875

e)2005.(x-2006)=2005

=>x-2006=1

=>x=2--7

g)[(x+50).50-50]:50=50

=>(x+50).50-50=1

=>(x+50).50=51

=>x+50=51.50=2550

=>x=2550-50

=>x=2500