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Evaluate ((-2)/(7)) ^(-4)xx ((-5)/(7)) ^...

Evaluate `((-2)/(7)) ^(-4)xx ((-5)/(7)) ^(2).`

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To evaluate the expression \(\left(-\frac{2}{7}\right)^{-4} \times \left(-\frac{5}{7}\right)^{2}\), we can follow these steps: ### Step 1: Apply the negative exponent rule The first part of the expression has a negative exponent. According to the rule of exponents, \(a^{-m} = \frac{1}{a^{m}}\). Therefore, we can rewrite \(\left(-\frac{2}{7}\right)^{-4}\) as: \[ \left(-\frac{2}{7}\right)^{-4} = \frac{1}{\left(-\frac{2}{7}\right)^{4}} = \frac{7^{4}}{(-2)^{4}} \] ### Step 2: Calculate \((-2)^{4}\) and \(7^{4}\) Now we calculate \((-2)^{4}\) and \(7^{4}\): \[ (-2)^{4} = 16 \quad \text{(since multiplying four negative twos gives a positive result)} \] \[ 7^{4} = 7 \times 7 \times 7 \times 7 = 2401 \] So we have: \[ \left(-\frac{2}{7}\right)^{-4} = \frac{2401}{16} \] ### Step 3: Evaluate \(\left(-\frac{5}{7}\right)^{2}\) Next, we evaluate the second part of the expression \(\left(-\frac{5}{7}\right)^{2}\): \[ \left(-\frac{5}{7}\right)^{2} = \frac{(-5)^{2}}{7^{2}} = \frac{25}{49} \] ### Step 4: Combine the results Now we can combine the two parts: \[ \left(-\frac{2}{7}\right)^{-4} \times \left(-\frac{5}{7}\right)^{2} = \frac{2401}{16} \times \frac{25}{49} \] ### Step 5: Multiply the fractions To multiply the fractions, we multiply the numerators and the denominators: \[ \frac{2401 \times 25}{16 \times 49} \] Calculating the numerator: \[ 2401 \times 25 = 60025 \] Calculating the denominator: \[ 16 \times 49 = 784 \] ### Step 6: Final result Thus, we have: \[ \frac{60025}{784} \] This fraction cannot be simplified further, so the final answer is: \[ \frac{60025}{784} \]
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