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What is the factored form of x2 − 4x − 5?

(x + 5)(x − 1)
(x + 5)(x + 1)
(x − 5)(x − 1)
(x − 5)(x + 1)

2 Answers

6 votes
Factored Form:
x^2 - 4x - 5
Simplifying:
x^2 + - 4x + - 5 = 0

Reorder the terms:
- 5 + - 4x + x^2 = 0

Solving for variable " x":
Subproblem 1:
Set the factor ( - 1 + - 1x) equal to Zero and attempt to solve.

Simplifying:
- 1 + - 1x = 0

Solving:
- 1 + - 1x = 0
Move all terms containing x to the left, all other terms to the right

Add 1 to each side of equation:
- 1 + 1 + - 1x = 0 + 1

Combine Like Terms: 0 + 1 = 1
x = - 1


Divide each side by - 1
x = - 1

Simplifying: x = - 1


Subproblem 2: Set the factor (5 + - 1x) equal to Zero attempt to solve

Simplifying:
5 + - 1x = 0

Move all terms containing x to the left, all other terms to the right
Add - 5 to each side of the equation
5 + - 5 + - 1x = 0 + 5

Combine Like terms: 5 + - 5 = 0
0 + - 1x = 0 + - 5
- 1x = 0 + - 5

Combine Like Terms: 0 + - 5 = - 5
- 1x = - 5

Divide each side by - 1
x = 5

Simplifying:
x = 5

Solution:
x = { - 1, 5}





Answer when factored:
(x + 1)(x - 5)







hope that helps!!!
User Nikhil Ranjan
by
5.1k points
3 votes

Answer:

D

Explanation:

User Abi
by
5.6k points