To combine like terms, add or subtract the coefficients (the numbers that come before the variables) of terms that have the same variable raised to the same exponent.

9a⁸ - 6a⁸ = 3a⁸

A cube is a rectangular solid box with a height (h), length (l), and width (w). The volume is h x l x w and the surface area is 2lw x 2wh + 2lh.

To solve this equation, repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

-c + 5 = -4 - 4c
-c = -4 - 4c - 5
-c + 4c = -4 - 5
3c = -9
c = \( \frac{-9}{3} \)
c = -3

An acute angle measures less than 90°, a right angle measures 90°, and an obtuse angle measures more than 90°.

You need to find the value of c so solve the first equation in terms of x:

-2c + x = -8
x = -8 + 2c

then substitute the result (-8 - -2c) into the second equation:

-9c - 1(-8 + 2c) = -1
-9c + (-1 x -8) + (-1 x 2c) = -1
-9c + 8 - 2c = -1
-9c - 2c = -1 - 8
-11c = -9
c = \( \frac{-9}{-11} \)
c = \(\frac{9}{11}\)