WGU QL Formulas

• Sum of the three angles for a triangle is <A + <B+ <C = 180
• Polygons
• Where n is the number of sides
• (n-2)*180

• Polygon - add up the length of all sides
• Rectangle = 2(L+W)
• Square = P = 4*s

• rectangles
• A=L*W
• Squares
• A=s²
• Paraellogram
• A=b*h
• Triangles
• A=1/2*b*h
• Trapezoids
• A=1/2*h*(a+b)

• Arithmetic
• Found by adding a common number to the first term and then to the second term etc. Find this common
• term by subtracting a 2nd number from 1st etc. Be sure to spot the pattern.

• To find the Nth term
• – use a formula

• Where
• a₁ = first term of sequence
• a_n = the term you wish to find
• d= common difference
• n – place position of the
• term IE Find term 20 – n = 20

a_n= a₁ + d(n-1)

Geometric Sequences

• Found by multiplying a common number from 1 term to the next. For example multiplying 3 by the first term and then multiplying 3 by the
• first number etc. Find the common ratio by problem solving and spotting the pattern.

Can do this by dividing the 2nd term by the first term – this is called the common ratio. Can use decimals or fractions.

• To find the Nth term – use a formula
• Use exponents ( r = common ratio)

a_n = a₁ x r ^n-1