Question

Can someone help me solv this.What is (3+sqrt(5)) (7-2sqrt(5))^2
a+b sqrt(5)

Answer 1

I'm not sure what this equation is suppose to look like. Do you mind using the 'equation' option in comments to write it out? :)

Answer 2

\[(3+\sqrt{5}) (7-2\sqrt{5})^{2}\]

Answer 3

Thanks! Okay, just give me a minute please..

Answer 4

Is this suppose to be simplified?

Answer 5

Yes
a+b \[\sqrt{5}\]

Answer 6

Okay well by simplifying, this is my answer.. \[67-35\sqrt{5}+4\times5^{\frac{ 3 }{ 2 }}\]

Answer 7

But I don't think that's what they are looking for. Do you have multiple choices?

Answer 8

all I got is the answer can be written as \[a+b \sqrt{5}\]

Answer 9

I've got it\[-15+67\sqrt{5}\]

Answer 10

Simplify \[(3+\sqrt{5}) (7-2\sqrt{5})^{2}\]
The answer can be written as \[a+b \sqrt{5}\]
I need to find a and b

I tried to use \[(a+b)^{2} = a^{2}+ 2ab +b^{2}\]
Messed it up somewhere and not sure how to solv it :/

Answer 11

I can show you the steps on how I got that answer but it's pretty long

Answer 12

Yes please, that would be super! :)
Forever thankful!

Answer 13

I'm going to put it in each step at a time, okay?\[(\sqrt{5}+3)((-2\times \sqrt{5})^{2}+2(-2\times \sqrt{5})7+7^{2})\]

Answer 14

\[(\sqrt{5}+3)((2\times \sqrt{5})^{2}-2\times2\times \sqrt{5}\times7+49)\]

Answer 15

\[(\sqrt{5}+3)(2^{2}(\sqrt{5})^{2}-2\times2\times7\times \sqrt{5}+49)\]

Answer 16

\[(\sqrt{5}+3)(4\times \sqrt[2]{5}-28\times \sqrt{5}+49)\]

Answer 17

\[(\sqrt{5}+3)(4\times5-28\times \sqrt{5}+49)\]

Answer 18

\[(\sqrt{5}+3)(-28\times \sqrt{5}+69)\]

Answer 19

\[-5\times28\times \sqrt{5}+\sqrt{5}\times69\times3\times28\times \sqrt{5}+3\times69\]

Answer 20

\[-28\times \sqrt[2]{5\times5}+69\times \sqrt{5}-84\times \sqrt{5}+207\]

Answer 21

\[-28\times \sqrt[2]{5^{1+1}}+69\times \sqrt{5}-84\times \sqrt{5}+207\]

Answer 22

Almost done, I promise

Answer 23

\[-28\times \sqrt[\frac{ 2 }{ 2 }]{5^{\frac{ 2 }{ 2 }}}+69\times \sqrt{5}-84\times \sqrt{5}+207\]

Answer 24

\[-28\times5+69\times \sqrt{5}-84\times \sqrt{5}+207\]

Answer 25

\[-140+69\times \sqrt{5}-84\times \sqrt{5}+207\]

Answer 26

\[-15\times \sqrt{5}+67\]
Put ^^ in the correct form\[(a+b \sqrt{x})\] and.. \[-15+67\sqrt{5}\]
Ta-da!! :)

Answer 27

Sorry that was super long :(

Answer 28

Thank you so much! And yes that was long, thanks for doing it, did you follow a specifc formula? What ever I did doesnt quite look like that.
Thanks again. :)