###
area of rectangle

length x width

###
perimeter of rectangle

(length + width) x 2

###
area of parallelogram

base x height

###
area of triangle

(base x height) ÷ 2

###
perimeter of triangle

side 1 + side 2 + side 3

###
area of circle

3.14 x radius x radius

###
circumference of circle

3.14 x diameter (3.14 x 2 x radius)

###
area of a square

side x side

###
perimeter of a square

4 x side

###
Scalene

A triangle with NO congruent sides

###
Isosceles

A triangle with TWO OR MORE congruent sides

###
Equilateral

A triangle with THREE congruent sides

###
Acute

A triangle with THREE acute angles

###
Obtuse

A triangle with ONE obtuse angle

###
Right

A triangle with ONE right angle

###
Equiangular

A triangle with THREE congruent angles (they are all 60°)

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