MAT10:8.3.1 SOLVING QUADRATIC EQUATIONS BY FACTORISATION

Solve the equation 5x² + 10x = 0

x = 2
x = 0 or x = – 2
x = 0 or x = 2

Solve the equation 2x² – 8x= 0

x = 0 or x = 4
x = 0 or x = – 4
x = 2 or x = -2

Solve the equation 3x² = 12x

x = 4
x = 4 or x = -4
x = 0 or x = 4

Solve the equation x² + 7x + 12 = 0

x = 3 or x = 4
x = – 3 or x = – 4
x = 3 or x = – 4

Solve the equation a² – 3a – 10 = 0

a = – 2 or a = 5
a = 2 or a = -5
a = – 2 or a = – 5

Solve the equation p² – 2p = 3

p = 3 or p = -1
p = -3 or p = – 1
p =- 3 or p = 1

Solve the equation x² = 8x – 15

x = – 3 or x = -5
x = 3 or x = 5
x = 3 or x = – 5

Solve the equation x² = 22 – 9x

x = – 2 or x = 11
x = – 2 or x = – 11
x = 2 or x = -11

Solve the equation x² = 6x + 7

x = – 7 or x = 1
x = 7 or x = 1
x = 7 or x = -1

Solve the equation x² + 36 = 12x

x = 6
x = 6 or x = – 6
x = 0 or x = -6

Solve the equation 2x² + 11x +12 = 0

x = 3/2 or 4
x =- 2/3 or – 4
x = -3/2 or x = – 4

Solve 3x² + 11x + 10 = 0

x = -5/3 or x = – 2
x = 5/3 or x = – 2
x = 5/3 or x = 2

Solve the equation 2x² – 11x + 15 = 0

x = – 5/2 or x = -3
x = 2/5 or x = 3
x = 5/2 or x = 3

Solve the equation 4x² – 20x + 21 = 0

x = 7/2 or x = 3/2
x = 2/7 or x = 2/3
x = – 7/2 or x = – 3/2

Solve the equation 4 + 4x – 3x²

x = – 2 or x = 2/3
x = 2 or x = – 2/3
x = 2 or x = – 3/2

Solve the equation 2x² = 7x + 9

x = – 9/2 or x = – 1
x = 2/9 or x = – 1
x = 9/2 or x = – 1

Solve the equation 3x² + 7x = 6

x = – 2/3 or x = 3
x = – 2/3 or x = – 3
x = 2/3 or x = – 3

Solve the equation 6x² = 15 – x

x = 5/3 or x = – 3/2
x = – 5/3 or x = – 3/2
x = – 5/3 or x = 3/2