To multiply binomials, use the FOIL method. FOIL stands for First, Outside, Inside, Last and refers to the position of each term in the parentheses.

An isosceles triangle has two sides of equal length. An equilateral triangle has three sides of equal length. In a right triangle, two sides meet at a right angle.

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.

8a x 9b = (8 x 9) (a x b) = 72ab

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 < sign and the answer on the other.

-5c + 7 < \( \frac{c}{1} \)
1 x (-5c + 7) < c
(1 x -5c) + (1 x 7) < c
-5c + 7 < c
-5c + 7 - c < 0
-5c - c < -7
-6c < -7
c < \( \frac{-7}{-6} \)
c < 1\(\frac{1}{6}\)

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.