A circle is a figure in which each point around its perimeter is an equal distance from the center. The radius of a circle is the distance between the center and any point along its perimeter. A chord is a line segment that connects any two points along its perimeter. The diameter of a circle is the length of a chord that passes through the center of the circle and equals twice the circle's radius (2r).

To multiply monomials, multiply the coefficients (the numbers that come before the variables) of each term, add the exponents of like variables, and multiply the different variables together.

(6a)(4ab) + (7a²)(5b)
(6 x 4)(a x a x b) + (7 x 5)(a² x b)
(24)(a¹⁺¹ x b) + (35)(a²b)
24a²b + 35a²b
59a²b

The area of a triangle is equal to ½ base x height:

a = ½bh
a = ½ x 8 x 9 = \( \frac{72}{2} \) = 36

The perimeter of a triangle is the sum of the lengths of its sides:

p = x + y + z
p = 15cm + 13cm + 5cm = 33cm

The coordinate grid is composed of a horizontal x-axis and a vertical y-axis. The center of the grid, where the x-axis and y-axis meet, is called the origin.