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35 votes
35 votes

4 √(28x) + √(63x = )what are the steps to solving this?

4 √(28x) + √(63x = )what are the steps to solving this?-example-1
User Julio Motol
by
3.0k points

1 Answer

14 votes
14 votes

We are given the following radical expression


4\sqrt[]{28z}+\sqrt[]{63z}

Let us simplify the expression.

Re-write the radicals as


4\sqrt[]{28z}+\sqrt[]{63z}=4\sqrt[]{4\cdot7z}+\sqrt[]{9\cdot7z}

Apply the product rule below


\sqrt[]{a\cdot b}=\sqrt[]{a}\cdot\sqrt[]{b}

So applying the above rule, the expression becomes


4\sqrt[]{4\cdot7z}+\sqrt[]{9\cdot7z}=4\sqrt[]{4}\cdot\sqrt[]{7z}+\sqrt[]{9}\cdot\sqrt[]{7z}

We know that 4 and 9 are perfect squares so the expression becomes


4\sqrt[]{4}\cdot\sqrt[]{7z}+\sqrt[]{9}\cdot\sqrt[]{7z}=4\cdot2\cdot\sqrt[]{7z}+3\cdot\sqrt[]{7z}=8\cdot\sqrt[]{7z}+3\cdot\sqrt[]{7z}

Finally, Combine the radicals


8\cdot\sqrt[]{7z}+3\cdot\sqrt[]{7z}=(8+3)\sqrt[]{7z}_{}=11\sqrt[]{7z}

Therefore, the simplified expression is


11\sqrt[]{7z}

User Jefry Dewangga
by
3.2k points
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