1
2(a+b)=62
a+b=31
axb=210
a=31-b
(31-b)b=210
31b-b²=210
b²-31b+210=0
(b-10)(b-21)=0
daca b=10 a=21
daca b=21 a=10
2 a²+(a+1)²=421
a²+a²+2ab+1=421
2a²+2a=420
a²+a-210=0
(a-14)(a-15)=0
a=14
a=15
3. a²+(a+1)²=365
a²+a²+2ab+1=365
2a²+2a=364
a²+a-182=0
(a-13)(a-14)=0
a=13
a=14
4.a(a+1)=a+a+1+305
a²+a=2a+306
a²-a-306=0
(a-17)(a-18)=0
a=17
a=18
5.a(a+5)=a+a+5+149
a²+5a=2a+154
a²+3a-154=0
(a+14)(a-11)=0
caz 1. a=-14 ⇒-14+5=-9
caz 2. a=11 ⇒11+5=16
verificare caz 1
(-14)x(-9)=126
-14-9=-23
126-(-23)=149
verificare caz 2
11x16=176
11+16=27
176-27=149
