Which of the following expressions are equivalent to 48a^3-75a? Select all that apply.

Answer 1) 3(48a^3-75a).
Answer 2) 3a(16a^2-25)
Answer 3)3a(4a+5)(4a+5)
Answer 4) 3a(4a+5)(4a-5)
Answer 5) -3a(25-16a^2)
Answer 6) -3a(5-4a)(5+4a)

The highest common factor is 3a That means that 48a^3 must be divided by 3a which means 48a^3 / 3a = 16a^2. Notice what happened. 48/3 = 16. a^3/a = a^2.

Now you have to pull out 3a from 75a. That wasn't done to Answer 1. So answer one is incorrect.

75a/3a = 25

So far what you answer looks like is

3a(16a^2 - 25) which is answer 2

===========================================

Answer 3 is wrong because one of the factor has to be - 5. Neither one is.

===========================================

Answer 4 is correct

16a^2 - 25 factors into (4a - 5)(4a + 5)

So what is written reflects those factors + the 3a

==============================================

Now we come to the brutal ones.

If you take out a minus sign from the brackets, it has the effect of turning the two terms inside the brackets around.

-3a(25 - 16a^2) is what the above sentence means. so 5 is correct

==============================================

The two terms inside the brackets still factor

-3a ( 5 - 4a)(5 + 4a) It is just that they are turned around.

6 is correct.

===============================================

Which of the following expressions are equivalent to 48a^3-75a? Select all that apply. Answer 1) 3(48a^3-75a). Answer 2) 3a(16a^2-25) Answer 3)3a(4a+5)(4a+5) Answer 4) 3a(4a+5)(4a-5) Answer 5) -3a(25-16a^2) Answer 6) -3a(5-4a)(5+4a)

Respuesta :

Otras preguntas

Which of the following expressions are equivalent to 48a^3-75a? Select all that apply.

Answer 1) 3(48a^3-75a).
Answer 2) 3a(16a^2-25)
Answer 3)3a(4a+5)(4a+5)
Answer 4) 3a(4a+5)(4a-5)
Answer 5) -3a(25-16a^2)
Answer 6) -3a(5-4a)(5+4a)