Решите уравнение x-20/x=1

Question

Решите уравнение x-20/x=1

Answer 1

X/20 - x = 1 / x
x² = 20 - x
x² + x - 20 = 0
D = b² - 4ac = 1² - 4 × 1 × ( - 20) = 1+ 80 = 81 =9²
x₁ = - 1 +9 / 2 = 4
x₂ = - 1 - 9 / 2 = - 5 

Answer 2

x-20/x=1
x²-20=1x
x²-x-20=0
D=1-4×1×(-20)=81
x1=(1-9)/2=-4
x2=(1+9)/2=5
Ответ: -4; 5