This is sometimes true because when distributing the sign could either be either minus or plus...
If you multiply a positive number with a negative number it will be negative. If you multiply a negative by a negative it will be positive. If you multiply a positive with a positive it will be positive.
Answer: 5
Step-by-step explanation: I got it right
Answer:
Refer below for detailed explanation.
Step-by-step explanation:
Standard equation:
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
P.s have attached the picture of quadratic formula as well.
Two-hundred forty thousand, five