Question

PLEASE HELP!
Simplify each product.
(2a^2+4a+5)(5a-4)

Answer 1

Well okay. Are you familiar with the distributive method of multiplication? If so, simply use it.

Answer 2

When multiplying the unknown constant, "a". Keep the power rule in mind. \[x^{a}(x^{b}) = x^{a + b}\]

Answer 3

After wards, simply add like terms and you have your answer.

Answer 4

alright so first i multiply 2a^2x5a?

Answer 5

Doesn't really matter what order you multiply in but yes, that's a good choice to start with.

Answer 6

10a^3+4a+25

Answer 7

does this look right? ;/

Answer 8

Hmm. seems like you missed a few things. Let's start with this. (2a^2+4a+5)(5a). Next you'll have to do:(2a^2+4a+5)(-4). Then add those two answers together.

Answer 9

so i multiply each of these numbers (2a^2 + 4a + 5) by 5? for example 2a^2 x 5 ; 4a x 5; 5 x 5

Answer 10

Well 5a...not 5.

Answer 11

10^a3+20^2+25a do i add these into one?

Answer 12

10a^3+20a^2+25a

Answer 13

There's nothing to add here. You can only add like terms. So do the second part of the equation: (2a^2+4a+5)(-4)

Answer 14

8a^2+16a+20

Answer 15

how do i add the like terms?

Answer 16

Check that answer again. What's a negative times a positive?

Answer 17

-2a^2+1a

Answer 18

What is that?

Answer 19

neg x a pos is a neg

Answer 20

Okay. So do (2a^2+4a+5)(-4) again.

Answer 21

-2a^2+a+1

Answer 22

-2a^2+8a+20

Answer 23

Why is it a -2a^2? You have -4 multiplying 2a^2.

Answer 24

-6

Answer 25

Okay. what's 4 x 2a^2?

Answer 26

8a^2

Answer 27

Right. Now you simply have a negative there. When you see one negative sign or an odd number of negative signs in a multiplication equation, that means that the resulting answer will be negative. When the number of negative signs are even, then the resulting answer will be positive. Everything else is done completely the same.

So -4 x 2a^2 would be what?

Answer 28

-8a^2
because its a negative number

Answer 29

Exactly. So everything else is done exactly the same, just make sure you keep track of the negative signs. So do (2a^2+4a+5)(-4)

Answer 30

After you get that done, simply add to the above answer of 10a^3+20a^2+25a. Add the terms that are similar. So terms with a power of 2 to terms with a power of 2. terms with a power of 1 to terms with a power of 1, etc.