scuze am rezolvat numai una, succesฅ^•ﻌ•^ฅ
Răspuns:
6,3
Explicație pas cu pas:
2×(3x +5)+5 =51
2 ×(3x +5) =51-5
2×(3x +5)=46
3x+5 =46:2
3x+5=23
3x=23 - 5
3x=18
x=18:3
x=6
5-[8×(7x - 16)-17]-16=99
5-[8×(7x - 16)-17]=99+16
5-[8×(7x - 16)-17]=115
8 ×(7x - 16)-17 =115 :5
8 ×(7x - 16) - 17 =23
8 ×(7x - 16) =23 +17
8 ×(7x - 16) =40
7x - 16 =40 :8
7x - 16 =5
7x =5 +16
7x =21
x=21 :7
x=3
