Simplifying 5 + -2(4a + 1) + 3a = 13 Reorder the terms: 5 + -2(1 + 4a) + 3a = 13 5 + (1 * -2 + 4a * -2) + 3a = 13 5 + (-2 + -8a) + 3a = 13 Combine like terms: 5 + -2 = 3 3 + -8a + 3a = 13 Combine like terms: -8a + 3a = -5a 3 + -5a = 13 Solving 3 + -5a = 13 Solving for variable 'a'. Move all terms containing a to the left, all other terms to the right. Add '-3' to each side of the equation. 3 + -3 + -5a = 13 + -3 Combine like terms: 3 + -3 = 0 0 + -5a = 13 + -3 -5a = 13 + -3 Combine like terms: 13 + -3 = 10 -5a = 10 Divide each side by '-5'. a = -2

6 0

3 years ago

A scientist wishes to estimate the mean breaking strength of a certain type of steel rod within 3.0 psi with 95% confidence. Bas

yaroslaw [1]

Answer:97 rods

Step-by-step explanation:

The number of steel rods for 95% confidence level

$n=\left ( \frac{Z_\frac{\alpha }{2}\times \hat{\sigma }}{E} \right )^2$