1) x^2-9=0
x^2=9
x=√9
x1=-3
x2=3
2) 121-x^2=0
121=x^2
x=√121
x1=-11
x2=11
3) 1,96 - у² = 0
(1,4-у)(1,4+у) = 0
1,4-у=0 или 1,4+у = 0
у=1,4 или у=-1,4
1) x^2-9=0
x^2=9
x=√9
x1=-3
x2=3
2) 121-x^2=0
121=x^2
x=√121
x1=-11
x2=11
3) 1,96 - у² = 0
(1,4-у)(1,4+у) = 0
1,4-у=0 или 1,4+у = 0
у=1,4 или у=-1,4