express $\displaystyle \sqrt{22.5} $ in the form $\displaystyle K\sqrt{10} $ I dont get how to do this, can some one show me? Thanks.
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Originally Posted by Tweety express $\displaystyle \sqrt{22.5} $ in the form $\displaystyle K\sqrt{10} $ I dont get how to do this, can some one show me? Thanks. Recall that $\displaystyle \sqrt{ab} = \sqrt{a} \sqrt{b}$ $\displaystyle \sqrt{a^2} = a$ $\displaystyle \sqrt{22.5} = K\sqrt{10} = \sqrt{10K^2}$ Square both sides: $\displaystyle 10K^2 = 22.5$ solve for K
$\displaystyle \sqrt{22.5} = \sqrt{2.25 \cdot 10} = \sqrt{2.25} \cdot \sqrt{10}$ So $\displaystyle K=\sqrt{2.25} = \frac{3}{2}$
Originally Posted by Tweety express $\displaystyle \sqrt{22.5} $ in the form $\displaystyle K\sqrt{10} $ I dont get how to do this, can some one show me? Thanks. Hi Tweety, Another approach: $\displaystyle \sqrt{22.5}=\sqrt{\frac{225}{10}}=15\sqrt{\frac{1} {10}}=\frac{15\sqrt{10}}{10}=\frac{3}{2}\sqrt{10}$
the correct answer is $\displaystyle \frac{3}{2}\sqrt{10} $ edit; oh right I get it now, thanks!
Originally Posted by Tweety the correct answer is $\displaystyle \frac{3}{2}\sqrt{10} $ edit; oh right I get it now, thanks! The square root of 2.25 is 1.5
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