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

a = l x w
a = a x b
a = 5 x 2
a = 10

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.

(7a)(3ab) + (9a²)(2b)
(7 x 3)(a x a x b) + (9 x 2)(a² x b)
(21)(a¹⁺¹ x b) + (18)(a²b)
21a²b + 18a²b
39a²b

An exterior angle of a triangle is equal to the sum of the two interior angles that are opposite:

d° = b° + c°

To find angle c, remember that the sum of the interior angles of a triangle is 180°:

180° = a° + b° + c°
c° = 180° - a° - b°
c° = 180° - 43° - 41° = 96°

So, d° = 41° + 96° = 137°

A shortcut to get this answer is to remember that angles around a line add up to 180°:

a° + d° = 180°
d° = 180° - a°
d° = 180° - 43° = 137°

The first step to solve a quadratic equation that's set to zero is to factor the quadratic equation:

z² - 4z - 5 = 0
(z + 1)(z - 5) = 0

For this expression to be true, the left side of the expression must equal zero. Therefore, either (z + 1) or (z - 5) must equal zero:

If (z + 1) = 0, z must equal -1
If (z - 5) = 0, z must equal 5

So the solution is that z = -1 or 5

The entire length of this line is represented by AD which is AB + BD:

AD = AB + BD