Question

Which factors can be multiplied together to make the trinomial 5x2 + 8x – 4? Check all that apply.

Answer 1

Answer:

x+2

5x-2

Step-by-step explanation:

There is only 2 binomials that will multiply together that will give the given trinomial.

ax^2+bx+c

5x^2+8x-4

Goal: Find two numbers that multiply to be a*c and add up to be b.

We will use this goal to factor our trinomial.

a=5

b=8

c=-4

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a*c=-20

b=8

Can you think of two numbers that multiply to be -20 and add up to be 8? I hope you said 10 and -2.

So we are going to replace 8x with -2x+10x.

5x^2+8x-4

5x^2-2x+10x-4

We are going to pair the first terms together and the second two terms together like so:

(5x^2-2x)+(10x-4)

Now we are going to factor each pair.

x(5x-2)+2(5x-2)

(5x-2)(x+2)

So (x+2) is a factor of the given trinomial and (5x-2) is a factor of the given trinomial.

Answer 2

Answer

x+2 and 5x-2

Step-by-step explanation: