Question

Find the sum and express it in simplest form
(7n^3-9n)+(-8n^3+6n-3)

Answer 1

Reorder the terms: 6(-6 + 2n) + -3(7n + -10) = -9n + n (-6 * 6 + 2n * 6) + -3(7n + -10) = -9n + n (-36 + 12n) + -3(7n + -10) = -9n + n Reorder the terms: -36 + 12n + -3(-10 + 7n) = -9n + n -36 + 12n + (-10 * -3 + 7n * -3) = -9n + n -36 + 12n + (30 + -21n) = -9n + n Reorder the terms: -36 + 30 + 12n + -21n = -9n + n Combine like terms: -36 + 30 = -6 -6 + 12n + -21n = -9n + n Combine like terms: 12n + -21n = -9n -6 + -9n = -9n + n Combine like terms: -9n + n = -8n -6 + -9n = -8n Solving -6 + -9n = -8n Solving for variable 'n'. Move all terms containing n to the left, all other terms to the right. Add '8n' to each side of the equation. -6 + -9n + 8n = -8n + 8n Combine like terms: -9n + 8n = -1n -6 + -1n = -8n + 8n Combine like terms: -8n + 8n = 0 -6 + -1n = 0 Add '6' to each side of the equation. -6 + 6 + -1n = 0 + 6 Combine like terms: -6 + 6 = 0 0 + -1n = 0 + 6 -1n = 0 + 6 Combine like terms: 0 + 6 = 6 -1n = 6 Divide each side by '-1'. n = -6 Simplifying n = -6

Answer 2

-n^3 -3n +3 is the answer
the Check the image for steps.