Answer:
3 and 4
Step-by-step explanation:
Well to start we have to know that they are asking us, a factorized form of a quadratic expression
a quadratic expression is of the form
ax ^ 2 + bx + c
Now the factored form is as follows
a ( x - x1 ) ( x - x2 )
Next, let's look at each of the options
In this case we lack a term with x since if we solve we have a linear equation
1. 5(x+9)
5x + 45
In this case if we pay attention they are being subtracted instead of multiplying, so we will not get a quadratic function
2. (x+4) - (x+6)
-2
In this case we have everything we need, now let's try to solve
3. (x-1) (x-1)
x^2 - x - x + 1
x^2 - 2x + 1 quadratic function
In this case we have everything we need, now let's try to solve
4. (x-3) (x+2)
x^2 -3x +2x -6
x^2 -x - 6 quadratic function
In this case we have a quadratic function but we do not have it in its factored form since we can observe the x ^ 2
5. x^2 + 8x
