A line on the coordinate grid can be defined by a slope-intercept equation: y = mx + b. For a given value of x, the value of y can be determined given the slope (m) and y-intercept (b) of the line. The slope of a line is change in y over change in x, \({\Delta y \over \Delta x}\), and the y-intercept is the y-coordinate where the line crosses the vertical y-axis.

A trapezoid is a quadrilateral with one set of parallel sides.

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 -18 as well and sum (Inside, Outside) to equal 3. For this problem, those two numbers are -3 and 6. Then, plug these into a set of binomials using the square root of the First variable (y²):

y² + 3y - 18
y² + (-3 + 6)y + (-3 x 6)
(y - 3)(y + 6)

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

c² = a² + b²
c² = 2² + 4²
c² = 4 + 16
c² = 20
c = \( \sqrt{20} \)

The volume of a cube is height x length x width:

v = h x l x w
v = 6 x 2 x 2
v = 24