Question

a, b = nr reale
aXb = 16
a : b = 4
a = ? , b=?

Answer 1

a×b=16
a:b=4
=> a=4b
a×b=4b×b=16
4b^2=16
b^2=16:4=4
b=√4
=> b=2
b= -2
Acum vom avea doua solutii si pentru a.
a×2=16
a=16:2=8

a×(-2)=16
a=16:(-2)= -8

VERIFICARE:
a=8, b=2
8×2=16
8:2=4

a= -8, b= -2
(-8)×(-2)=16
(-8):(-2)=4

Answer 2

a·b=16;
a:b=4=>a=4b;
Inlocuim in a·b=16 pe a cu 4b:
4b·b=16;
4b^2=16;
b^2=16:4
b^2=4;
b=¬/4;
b=2;
=>a=4·2=8;

Verificare:8·2=16;
8:2=4;

P.S. ^2 inseamna la patrat
si ¬/ inseamna radical