There are 4 2-passenger taxis available so that's 4 x 2 = 8 total seats. There are 13 people needing transportation leaving 13 - 8 = 5 who will have to find other transportation.

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

To multiply terms with radicals, multiply the coefficients and radicands separately:

6\( \sqrt{7} \) x 4\( \sqrt{7} \)
(6 x 4)\( \sqrt{7 \times 7} \)
24\( \sqrt{49} \)

Now we need to simplify the radical:

24\( \sqrt{49} \)
24\( \sqrt{7^2} \)
(24)(7)
168

A number in scientific notation has the format 0.000 x 10^exponent. To convert to scientific notation, move the decimal point to the right or the left until the number is a decimal between 1 and 10. The exponent of the 10 is the number of places you moved the decimal point and is positive if you moved the decimal point to the left and negative if you moved it to the right:

0.0004675 in scientific notation is 4.675 x 10^-4

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

-6z³ + 5z³
(-6 + 5)z³
-z³