When 5 radical 20 is written in simplest form, the result is k radical 5. What is the value of k?
A ali1 New member Joined Jan 27, 2010 Messages 1 Jan 27, 2010 #1 When 5 radical 20 is written in simplest form, the result is k radical 5. What is the value of k?
M masters Full Member Joined Mar 30, 2007 Messages 378 Jan 27, 2010 #2 ali1 said: When 5 radical 20 is written in simplest form, the result is k radical 5. What is the value of k? Click to expand... Hi ali1, Simplify: \(\displaystyle 5\sqrt{20}\) We want to factor out the largest perfect square factor of the radicand, if it has one. Fortunately, this one has one. The radicand (20) can be factored into 4 times 5. Now let's restate it this way: \(\displaystyle 5\sqrt{4\cdot 5}\) This way, we can extract the square root of 4 and bring it to the outside of the radical and leave the 5 inside. \(\displaystyle 5\cdot 2\sqrt{5}\) Looks like your value of k is intuitively obvious to the most casual observer.
ali1 said: When 5 radical 20 is written in simplest form, the result is k radical 5. What is the value of k? Click to expand... Hi ali1, Simplify: \(\displaystyle 5\sqrt{20}\) We want to factor out the largest perfect square factor of the radicand, if it has one. Fortunately, this one has one. The radicand (20) can be factored into 4 times 5. Now let's restate it this way: \(\displaystyle 5\sqrt{4\cdot 5}\) This way, we can extract the square root of 4 and bring it to the outside of the radical and leave the 5 inside. \(\displaystyle 5\cdot 2\sqrt{5}\) Looks like your value of k is intuitively obvious to the most casual observer.
mmm4444bot Super Moderator Joined Oct 6, 2005 Messages 10,902 Jan 27, 2010 #3 First, you need to be able to simplify radicals. Do you know how to simplify \(\displaystyle \sqrt{20}\) ?
First, you need to be able to simplify radicals. Do you know how to simplify \(\displaystyle \sqrt{20}\) ?