The area of a rectangle is equal to its length x width:

a = l x w
a = a x b
a = 3 x 4
a = 12

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.

-6c - 4 = \( \frac{c}{5} \)
5 x (-6c - 4) = c
(5 x -6c) + (5 x -4) = c
-30c - 20 = c
-30c - 20 - c = 0
-30c - c = 20
-31c = 20
c = \( \frac{20}{-31} \)
c = -\(\frac{20}{31}\)

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.

(3a)(7ab) + (3a²)(6b)
(3 x 7)(a x a x b) + (3 x 6)(a² x b)
(21)(a¹⁺¹ x b) + (18)(a²b)
21a²b + 18a²b
39a²b

A quadrilateral is a shape with four sides. The perimeter of a quadrilateral is the sum of the lengths of its four sides.

A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The volume of a cylinder is π r²h and the surface area is 2(π r²) + 2π rh.