The least common multiple (LCM) is the smallest positive integer that is a multiple of two or more integers.

To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:

-4c⁷ - 5c⁷
(-4 - 5)c⁷
-9c⁷

To multiply fractions, multiply the numerators together and then multiply the denominators together:

\( \frac{4}{9} \) x \( \frac{4}{5} \) = \( \frac{4 x 4}{9 x 5} \) = \( \frac{16}{45} \) = \(\frac{16}{45}\)

To simplify a radical, factor out the perfect squares:

\( \sqrt{12} \)
\( \sqrt{4 \times 3} \)
\( \sqrt{2^2 \times 3} \)
2\( \sqrt{3} \)

To take the square root of a fraction, break the fraction into two separate roots then calculate the square root of the numerator and denominator separately:

\( \sqrt{\frac{16}{16}} \)
\( \frac{\sqrt{16}}{\sqrt{16}} \)
\( \frac{\sqrt{4^2}}{\sqrt{4^2}} \)
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