How do you evalaute $\sqrt { 45} \times \sqrt { 64}$ ?

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Answer 1 · 2018-05-05T09:55:20

$24sqrt5$

$sqrt45 times sqrt64 = sqrt(9*5) times sqrt(8*8) = 3sqrt5 times8 = 24sqrt5$

Answer 2 · 2018-05-05T10:01:49

$24*\sqrt(5)$

$\sqrt(45)*\sqrt(64)$

Write both numbers as a product of prime numbers .
(unique factorization).

$45=5*9=5*3*3$
$64=2*32=2*2*16=2*2*2*8=2*2*2*2*4=$
$=2*2*2*2*2*2=2^6$

$\sqrt(45)*\sqrt(64)=$

$=\sqrt(5*3*3)*\sqrt(2^6)=$

$=\sqrt(5*3^2)*2^(6/2)=$

$=\sqrt(5)*\sqrt(3^2)*2^3=$

$=\sqrt(5)*3*8=$

$=24*\sqrt(5)$

How do you evalaute \sqrt { 45} \times \sqrt { 64}\sqrt { 45} \times \sqrt { 64}?