The standard formula for a quadratic is
An example of this would be
Factorising quadratics when a is equal to 1
In order to solve the quadratic, you need to put it into the standard format: ax²+bx+c=0. The factorising method goes as follows:
1) ALWAYS rearrange into the STANDARD FORMAT : ax²+bx+c=0
2) Find the factors of a and c in order to factorise
3) Use the table in order to work out the factorised form of the equation.
4) Find the actual solution to the equations.
"solve x²-x=12 by factorising"
1) Rearrange the equation into the standard format:
x²-x=12 (minus 12 from both sides)
x²-x-12=0 (now in the standard format)
2) ac= 1x-12 = -12 : we now need to find the factors of -12 and list them. The answer must multiply to make -12 and add/subtract to make b. In this case, b is equal to -1.
Factors of -12:
1 and -12
2 and -6
3 and -4
REMEMBER: Write the factors at first as if they were making positive ac (in this case 12). Then put the signs into the right side so…