Question

determina termenul necunoscut din egalitatile urmatoare


a) 3.a+5).5-3=292








b) (b -5).2=30








c) (c-17).3+15=45








d) [ 2.(d-30)-45 ].3=165






dau coroana

Answer 1

a)
(3xa+5)x5-3=292
(3xa+5)x5=292+3
3xa+5=295:5
3xa+5=59
3xa=59-5
3xa=54
a=54:3
a=18

b)
(b-5)x2=30
b-2=30:2
b-2=15
b=15+2
b=17

c)
(c-17)x3+15=45
(c-17)x3=45-15
(c-17)x3=30
c-17=30:3
c-17=10
c=10+17
c=27

d)
[2x(d-30)-45]x3=165
2x(d-30)-45=165:3
2x(d-30)-45=55
2x(d-30)=55+45
2x(d-30)=100
d-30=100:2
d-30=50
d=50+30
d=80