Question

Dacă a + b=4,5 şi a - b=0,5, află a şi b.

Answer 1

a+b=4.5⇒a=4.5-b

a-b=0.5⇒4.5-b-b=0.5
-2b=-4⇒b=2

a+b=4.5⇒a+2=4.5⇒a=2.5

Answer 2

a= 4.5-b
4.5-b-b=0.5
4.5-0.5=2b
4=2b
b=2
a=2.5

a+b=2.5+2=4.5
a-b=2.5-2=0.5