Пошаговое объяснение:
{2x + 2y = 70
{x.y = 300
2x + 2y = 70
x + y = 35
x = 35 - y
x.y = 300
(35 - y).y = 300
- y² + 35y - 300 = 0
∆ = 35² - 4.(- 1).(- 300)
∆ = 1225 - 1200
∆ = 25
x' = (- 35 + 5)/(2.(- 1))
x' = 30/2
x' = 15
x" = (- 35 - 5)/(2.(- 1))
x" = 40/2
x" = 20
x' = 35 - y'
- y' + 35 = 15
- y' = 15 - 35
- y' = - 20
y' = 20
x" = 35 - y"
- y" + 35 = 20
- y" = 20 - 35
- y" = - 15
y" = 15
Dimention: 20 x 15
Пошаговое объяснение:
{2x + 2y = 70
{x.y = 300
2x + 2y = 70
x + y = 35
x = 35 - y
x.y = 300
(35 - y).y = 300
- y² + 35y - 300 = 0
∆ = 35² - 4.(- 1).(- 300)
∆ = 1225 - 1200
∆ = 25
x' = (- 35 + 5)/(2.(- 1))
x' = 30/2
x' = 15
x" = (- 35 - 5)/(2.(- 1))
x" = 40/2
x" = 20
x' = 35 - y'
- y' + 35 = 15
- y' = 15 - 35
- y' = - 20
y' = 20
x" = 35 - y"
- y" + 35 = 20
- y" = 20 - 35
- y" = - 15
y" = 15
Dimention: 20 x 15