X² - X = 72
X² - X - 72 = 0
Δ = (-1)² - 4×1×(-72) = 1 + 288 = 289
X1 = (1+17)/2 = 18/2 = 9 SOLUTIE
X2 = (1-17)/=(-16)/2 = -8 ∉N NU ESTE SOLUTIE
2 × 2^X × 3^X = 432
(2×3)^X = 432÷2
6^X = 216
6^X = 6³
X=3
2^(X-5) × (2° + 2 - 2² - 2³ + 2^4 + 2^5) = 156
2^(X-5) × (1 + 2 - 4 - 8 + 16 + 32) = 156
2^(X-5) × 39 = 156
2^(x-5) = 156÷39
2^(X-5) = 4
2^(X-5) = 2²
X-5=2
X=2+5
X=7
