Answer:
Refer below for detailed explanation.
Step-by-step explanation:
1. ax^2+bx+c=0.
Quadratic formula:
2. x = -b+-sqrt(b^2-4ac)/2a. .
Now two equations to find the factored form through these formulas above.
Through this identifying a,b and c.
ax^2+bx+c=0.
x^2+4x-21=0
Here a=1, b=4, and c= -21
Now applying in the quadratic formula.
x=-4+-sqrt(4^2-4(1)(-21))/2(1)
Now solve it and it becomes
x=3 or x= -7.
Another example :
x^2+3x-4=0
Here a=1, b=3 and c=-4.
X=-3+-sqrt(3^2-4(1)(-4))/2(1)
Now solve it and
x= -4 and x=1