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.

(4a)(5ab) - (8a²)(3b)
(4 x 5)(a x a x b) - (8 x 3)(a² x b)
(20)(a¹⁺¹ x b) - (24)(a²b)
20a²b - 24a²b
-4a²b

The slope of this line is the change in y divided by the change in x. The endpoints of this line segment are at (-2, 6) and (2, 0) so the slope becomes:

The circumference of a circle is the distance around its perimeter and equals π (approx. 3.14159) x diameter: c = π d. The area of a circle is π x (radius)² : a = π r².

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

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° - 56° - 25° = 99°

So, d° = 25° + 99° = 124°

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° - 56° = 124°