Simplify the expression. [(–5)–7 (–5)8]3

1 answer:

3 0

$\bf [(-5)^{-7}(-5)^8]^3\implies \left[(-5)^{-7+8} \right]^3\implies \left[ (-5)^1 \right]^3
\\\\\\
(-5)^{1\cdot 3}\implies (-5)^3\implies (-5)(-5)(-5)\implies -125$

You might be interested in

What is 0.66666666666 as a fraction

stellarik [79]

To turn $0.(6)=0.6666...$ into a fraction you should do such steps:

1 step. Set up an equation by representing the repeating decimal with a variable. Using your example, you will let x represent the repeating decimal 0.(6), so you have x=0.666... .

2 step. Identify how many digits are in the repeating pattern, or n digits. Multiply both sides of the equation from Step 1 by $10^n$ to create a new equation. Again, using your example, you see that the repeating pattern consists of just one digit: 6. Now multiply both sides of the equation by $10^1 = 10$ . Thus, you have $10x = 10 \cdot 0.666...$ or $10x = 6.666....$ .

3 step. Subtract the equation in Step 1 from the equation in Step 2. Notice that when we subtract these equations, our repeating pattern drops off. Therefore, $10x-x=6.666...-0.666...\\ 9x=6$ .

4 step. You now have an equation that you can solve for x and simplify as much as possible, using x as a fraction: $9x = 6$ . If you divide both sides by 9, you get $x=\dfrac{6}{9}$ . When simplified, you get that $x=\dfrac{2}{3}$ .