I've been working on these problems for a little over an hour and i can't for the life of me figure out how to do them. Can someone walk me through these? Hopefully I'll start to get the hang of it.

1.) (-2 √15)(4 √21)

2.) 3∛128+5∛16

3.) √(50x4)

1.) (-2 √15)(4 √21)

2.) 3∛128+5∛16

3.) √(50x4)

These depend on the directions instructing to keep in simplest radical form

or take to a decimal. These answers will be in simplest radical form.

1.) (-2√15)(4√21)

= -8√315 {multiply}

= -8√9 √35 {depending on the directions whether to take to a decimal or not}

= -8(3)√35 {square root o{f 9 is 3}

= -24√35 {multiply}

2.) 3∛128+5∛16

==3∛64 ∛2) + 5∛8 ∛2 {break down the cube roots again directions dependent}

= 3(4)∛2 {cube root of 64 is 4}

= 12∛2 {multiply 3 by 4}

3.) √50x4

=√25x4√2 {group the perfect squares together under one square root sign}

= 5x2√2 {take the square root of 25x4}

- Algebra House

or take to a decimal. These answers will be in simplest radical form.

1.) (-2√15)(4√21)

= -8√315 {multiply}

= -8√9 √35 {depending on the directions whether to take to a decimal or not}

= -8(3)√35 {square root o{f 9 is 3}

= -24√35 {multiply}

2.) 3∛128+5∛16

==3∛64 ∛2) + 5∛8 ∛2 {break down the cube roots again directions dependent}

= 3(4)∛2 {cube root of 64 is 4}

= 12∛2 {multiply 3 by 4}

3.) √50x4

=√25x4√2 {group the perfect squares together under one square root sign}

= 5x2√2 {take the square root of 25x4}

- Algebra House