Explicație pas cu pas:
a)14 552+23×(46+75)-a=4 812
14 552+23×121-a=4 812
14 552+2 783-a=4 812
17 335-a=4 812
a=17 335-4 813
a=12 523
v:14 552+23×(46+75)-12 523=
14 552+23×121-12 523=
14 552+2 783-12 523=
17 335-12 523=
4 812
b)491+d+47×47-718=5 836
491+d+2 209-718=5 836
491+d+2 209=5 836+718
491+d+2 209=6 554
491+d=6 554-2 209
491+d=4 345
d=4 345-491
d=3 854
v:491+3 854+47×47-718=
491+ 3 854+2 209-718=
4 345+2 209-718=
6 54-718=
5 836
c)420:(215-1000-b)+24×7=170
420:(215-1 000-b)+168=170
420:(-785-b)+168=170
420:(-785-b)=170-168
420:(-785-b)=2
420:-785-b=2
-785-b=420:2
-785-b=210
b=-785-210
b=-995
Răspuns:
[tex]a)\:14562+23*(46+75) - a=4812\\\\14562 + 23*121 - a = 4812\\\\14562 + 2783 - a = 4812\\\\17345 -a = 4812\\\\17345 = 4812 +a\\\\17345 -4812 = a\\\\ \boxed{a =12533}[/tex]
b)
[tex]491+d+47*47-718=5836\\\\491+d+2209-718=5836\\\\d+1982 = 5836\\\\d = 5836-1982\\\\ \boxed{d = 3854}[/tex]
c)
[tex]420:(215-1000:b) +24*7=170\\\\420:(215-1000:b) +168=170\\\\420:(215-1000:b)=170-168\\\\420:(215-1000:b) = 2\\\\420 =2 * (215-1000:b)\\\\420 = 430-2000:b\\\\420+2000:b = 430\\\\2000:b = 430-420\\\\2000:b = 10\\\\2000=10b\\\\b = 2000:10\\\\\boxed{b = 200}[/tex]
