According to the Pythagorean theorem, the hypotenuse squared is equal to the sum of the two perpendicular sides squared:

c² = a² + b²
c² = 3² + 5²
c² = 9 + 25
c² = 34
c = \( \sqrt{34} \)

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.

8a - 4a = 4a

To factor a quadratic expression, apply the FOIL method (First, Outside, Inside, Last) in reverse. First, find the two Last terms that will multiply to produce 40 as well and sum (Inside, Outside) to equal -13. For this problem, those two numbers are -8 and -5. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² - 13y + 40
y² + (-8 - 5)y + (-8 x -5)
(y - 8)(y - 5)

The Pythagorean theorem defines the relationship between the side lengths of a right triangle. The length of the hypotenuse squared (c²) is equal to the sum of the two perpendicular sides squared (a² + b²): c² = a² + b² or, solved for c, \(c = \sqrt{a + b}\)

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.