Question

Stiind ca x=14,calculati a+b in fiecare din cazurile:
b) 11×a + 11×b +56+x=1170
c)7×a+7×b+7×x=700

Answer 1

11a+11b+54+x=1170

11a+11b+54+14=1170

11a+11b+68=1170

11a+11b=1170-68

11a+11b=1102

11(a+b)=1102

a+b=1102:11

a+b=100,(18)

7a+7b+7x=700

7a+7b+7*14=700

7a+7b+98=700

7a+7b=602

7(a+b)=602

a+b=86

Answer 2

x=14

a+b=?

b) 11×a + 11×b +56+x=1170

11(a+b)+56+14=1170

11(a+b)=1170-(56+14)

a+b=1100:11

a+b=100

c) 7×a+7×b+7×x=700

7(a+b+1)x14=700

7(a+b+1)x14=700:7

2(a+b+1)=100

a+b+1=100:2

a+b=50-1

a+b=49

Succes!