Solving Quadratics 2
Maths: Edexcel IGCSE Higher, topic 2.4.2
Solving Quadratics - Complete the Square
Complete the square to find solutions to x2 + 6x + 4 = 0:
Write the equation
Complete the square
Rearrange
Square root
Rearrange for x
These are the two solutions
Completing the Square
Completing the square for y = 2x2 + 12x + 5:
Write the equation
Factor out the x² term
Half the x coefficient and put it in the bracket like this
Expand
We need to minus 13 from the red equation to get the purple
Test yourself on Solving Quadratics 2
What can be used to solve quadratics?