Question

ex. 3 va rog!
Dau coroana si 20 pct!

Answer 1

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

b)
(b - 5) × 2 = 30
b - 5 = 30 : 2
b - 5 = 15
b = 15+5
b = 20

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

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