Question

If u answer this question i will give u 20 points and mark as brainliest

Answer 1

Answer=√5

Step by step explanation

$\\\\\implies\sf \sqrt{45} - 3 \sqrt{20} + 4 \sqrt{5} \\ \\ \implies\sf \sqrt{3 \times 3 \times 5} - 3\sqrt{2 \times 2 \times 5} + 4 \sqrt{5} \\ \\ \implies\sf \sqrt{ {3}^{2} \times 5 } - 3 \sqrt{ {2}^{2} \times 5 } + 4 \sqrt{5} \\ \\\implies\sf 3 \sqrt{5} - 3 \times 2 \sqrt{5 } + 4 \sqrt{5} \\ \\ \implies\sf3 \sqrt{5} - 6 \sqrt{5} + 4 \sqrt{5} \\ \\ \implies\sf 7 \sqrt{5} - 6 \sqrt{5} \\ \\ \implies\sf \sqrt{5}$

$\sf \sqrt{45} - 3 \sqrt{20} + 4 \sqrt{5} = \pink{ \sqrt{5}}$

Laws of exponents

$\begin{gathered}~~~~\begin{gathered}\sf {a}^{m} \times {a}^{n} = {a}^{m + n} \: \: \: \: \: \: \: \: \: \: \sf {a}^{m} \div {a}^{n} = {a}^{m - n} \\ \sf{( {a}^{m} ) ^{n} = {a}^{mn} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: a {}^{m} \times {n}^{m} = (ab) ^{m} } \\ \sf{a}^{0} = 1 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: {\frac{ {a}^{m} }{ {b}^{m} }= \left( \frac{a}{b} \right) ^{m} }\\\\\end{gathered}\end{gathered}$