ա/ {x^2=y {y-2=2
y=x^2
x^2-2=2
x^2=4
x=V4=2
2^2=y=4
(+-2;4)
բ/ {y^2-1=x {x-13=11
x-13=11
x=11+13=24
y^2-1=24
y^2=25
y=V25=5
(24;+-5)
գ/ {x-3=2 {y^2-x=4
x=2+3=5
y^2-5=4
y^2=4+5=9
y=V9=3
(5;+-3)
ա/ {x+y=3 {xy=-40
x+y=3
x=3-y
(3-y)y=-40
3y-y^2=-40
-y^2+3y=-40
y^2-3y-40=0
D=9-4*1*(-40)=169=13
y1=3+13/2=8
y1=3-13/2=-5
x=3-8=-5
x=3-(-5)=8
բ/ {x+y=7 {xy=12
x=7-y
(7-y)y=12
7y-y^2=12
-y^2+7y=12
y^2-7y+12=0
D=49-4*1*12=1
y1=7-1/2=3
y2=7+1/2=4
x=7-3=4
x=7-4=3
գ/ {x+y=3 {xy=-28
x=3-y
(3-y)y=-28
3y-y^2=-28
-y^2+3y=-28
y^2-3y+28=0
D=9-4*1*28=-19
Լուծում չունի
ա/ {x^2+y^2=41 {y-x=1
y=1+x
x^2+1+x^2=41
2x^2=40
x^2=20
x=V20
y=1V20
բ/ {x^2+y^2=13 {y-x=-1
-x=-1+y
x=1-y
1+y^2+y^2=13
2y^2=14
y^2=7
y=V7
x=1-V7
գ/ {x^2-y^2=3 {x+y=1
y=1-x
x^2-1+x^2=3
2x^2=4
x^2=2
x=V2
y=1-V2
ա/ {x^2-y^2=0 {y+x=0
y=0-x
x^2-0+x^2=0
2x^2=0
x^2=0
x=V0=0
y=0-0=0
բ/ {x^2-y^2=0 {y-x=0
y=0+x
x^2-0+x^2=0
2x^2=0
x^2=0
x=0
y=0
գ/ {x+y=0,2 {x^2-y^2=2
y=0,2-x
x^2-0,2+x^2=2
2x^2=2+0,2=2,2
x^2=1,1
x=V1,1
y=0,2-V1,1