91Ó°ÊÓ

Perform the indicated computations. Write the answers in scientific notation. If necessary, round the decimal factor in your scientific notation answer to two decimal places. $$\left(6.1 \times 10^{-8}\right)\left(2 \times 10^{-4}\right)$$

Explain how to add or subtract rational expressions with the same denominators.

Simplify each algebraic expression. $$5(3 y-2)-(7 y+2)$$

Explain how to add rational expressions having no common factors in their denominators. Use \(\frac{3}{x+5}+\frac{7}{x+2}\) in your explanation.

Simplify each algebraic expression. $$4(5 y-3)-(6 y+3)$$

In Exercises \(91-100,\) simplify using properties of exponents. $$\left(3 x^{\frac{2}{3}}\right)\left(4 x^{\frac{3}{4}}\right)$$

Factor completely, or state that the polynomial is prime. $$2 x^{3}-98 a^{2} x+28 x^{2}+98 x$$

Perform the indicated computations. Write the answers in scientific notation. If necessary, round the decimal factor in your scientific notation answer to two decimal places. $$\left(5.1 \times 10^{-8}\right)\left(3 \times 10^{-4}\right)$$

Perform the indicated computations. Write the answers in scientific notation. If necessary, round the decimal factor in your scientific notation answer to two decimal places. $$\left(4.3 \times 10^{8}\right)\left(6.2 \times 10^{4}\right)$$

In Exercises \(91-100,\) simplify using properties of exponents. $$\frac{20 x^{\frac{1}{2}}}{5 x^{\frac{1}{4}}}$$