Răspuns :
5ˣ⁺² + 5ˣ⁺¹ - 5 = 145
5ˣ⁺¹(5¹ + 5⁰) = 145 + 5
5ˣ⁺¹ * (5 + 1) = 150
5ˣ⁺¹ * 6 = 6 * 5² | : 6
5ˣ⁺¹ = 5²
x + 1 = 2
x = 2 - 1
x = 1
5ˣ⁺¹(5¹ + 5⁰) = 145 + 5
5ˣ⁺¹ * (5 + 1) = 150
5ˣ⁺¹ * 6 = 6 * 5² | : 6
5ˣ⁺¹ = 5²
x + 1 = 2
x = 2 - 1
x = 1
5 ^ X+2 + 5 ^ X+1 - 5 = 145
5^X+2 + 5 ^X+1 = 145 + 5
5^X+2 + 5 ^X+1 = 150
5 ^ X+1 × ( 5 + 1) = 150
5^ X+1 × 6 = 150
5^X+1 = 150 : 6
5^X+1 = 25
5^X+1 = 5^2
X + 1 = 2
X = 2-1
X = 1
5^X+2 + 5 ^X+1 = 145 + 5
5^X+2 + 5 ^X+1 = 150
5 ^ X+1 × ( 5 + 1) = 150
5^ X+1 × 6 = 150
5^X+1 = 150 : 6
5^X+1 = 25
5^X+1 = 5^2
X + 1 = 2
X = 2-1
X = 1