Question

Tentukan nilai a, b dan c dari persamaan kuadrat berikut Gunakan Rumus Abc :
a. x² + 5x - 5 =0
b. 2x² - 10x = 0

Answer 1

A) x² + 5x - 5 = 0
a = 1 ; b = 5 ; c = - 5

x₁,₂ = (-b +- √(b² - 4ac))/2a
= (- 5 +- √(25 + 20))/2
= (- 5 +- √45)/2
x₁ = (- 5 + 3√5)/2
x₂ = (- 5 - 3√5)/2

b) 2x² - 10x = 0
a = 2 ; b = - 10 ; c = 0

x₁,₂ = (- b +- √(b² - 4ac))/2a
= (10 +- √(100))/4
= (10 +- 10)/4
x₁ = (10 + 10)/4 = 5
x₂ = (10 - 10)/4 = 0

Answer 2

A) x² + 5x - 5 = 0
a = 1 ; b = 5 ; c = - 5

x₁,₂ = (-b +- √(b² - 4ac))/2a
= (- 5 +- √(25 + 20))/2
= (- 5 +- √45)/2
x₁ = (- 5 + 3√5)/2
x₂ = (- 5 - 3√5)/2

b) 2x² - 10x = 0
a = 2 ; b = - 10 ; c = 0

x₁,₂ = (- b +- √(b² - 4ac))/2a
= (10 +- √(100))/4
= (10 +- 10)/4
x₁ = (10 + 10)/4 = 5
x₂ = (10 - 10)/4 = 0