Question

8.4 add, subtract, and multiply radical expressions
score: 9.8/22 answered: 10/22
question 11
simplify.
5\sqrt{45z}+2\sqrt{80z}=
question help: video written example
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Explanation:

Step1: Simplify $\sqrt{45z}$

$\sqrt{45z}=\sqrt{9\times5z}=3\sqrt{5z}$

Step2: Simplify $\sqrt{80z}$

$\sqrt{80z}=\sqrt{16\times5z}=4\sqrt{5z}$

Step3: Substitute simplified radicals

$5\sqrt{45z}+2\sqrt{80z}=5\times3\sqrt{5z}+2\times4\sqrt{5z}$
$ = 15\sqrt{5z}+8\sqrt{5z}$

Step4: Combine like - terms

$(15 + 8)\sqrt{5z}=23\sqrt{5z}$

Answer:

$23\sqrt{5z}$