Which expression is equivalent to 9x^5+3x(4x^4-3x^2)^2

Question

asked Oct 14, 2018 224k views

2 Answers

Dignoe · Answer 1 · 2018-10-15T01:41:36+0000

Answer:

D. 48x^9-72x^7+36x^5

Explanation:

Just took it. Edg 2020. Hope this helps :)

Btw Look at you doing your school work looking smart! I see youuu! (even if you are cheating a lil but its ok im doing the same xD)

Barney Stinson · Answer 2 · 2018-10-17T13:08:10+0000

Answer:

48x^9-72x^7+36x^5

Explanation:

The initial expression is:

9x^5+3x(4x^4-3x^2)^2

First expand the squared part (inside the parenthesis):

$9x^5+3x(4x^4-3x^2)(4x^4-3x^2)\\9x^5+3x(16x^8-24x^6+9x^4)\\$

Then, multiply the terms inside the parenthesis by 3x applying the distributive property:

$9x^5+3x(16x^8-24x^6+9x^4)\\9x^5+48x^9-72x^7+27x^5$

Finally add terms with the same exponent

48x^9-72x^7+36x^5