665, 664, 659

x² + (x + 1)² + (x + 2)² = 302

x² + x² + 2x + 1 + x² + 4x + 4 = 302

3x² + 6x + 5 — 302 = 0

3x² + 6x — 297 = 0

x² + 2x — 99 = 0

D = 4 + 396 = 400

X₁ = -2 + 20 / 2 = 9
X₂ = -2 — 20 / 2 = -11

81 + 100 + 121 = 302
121 + 100 + 81 = 302

x * (x + 4) = 60

x² + 4x = 60

x² + 4x — 60 = 0

D = 16 + 240 = 256

X₁ = -4 + 16 / 2 = 6
X₂ = -4 — 16 / 2 = -10

x = 6

x + 4 = 10

P = 6 + 6 + 10 + 10 = 32

ա)

x * 3x/4 = 48

3x²/4 = 48/1

3x² = 192

x² = 64

x = 8

3x/4 = 6
P = (6 + 8) * 2 = 28

բ)

x * (x — 3) = 10

x² — 3x — 10 = 0

D = 9 + 40 = 49

X₁ = 3 + 7 / 2 = 5
X₂ = 3 — 7 / 2 = -2

x = 5