Area of triangles and quadrilaterals worksheet for Geometry
Five formulas, and four of them are a base times a height with or without a half. The trapezoid averages its two bases first; the rhombus uses its diagonals instead.
Also taught in Pre-Algebra, at its own level and with its own examples.
Not quite the one you need? Same words, different skill:
Find the area of a trapezoid with bases 6and 10 and height 4
Average the two bases: 8.
Multiply by the height.
The answer is 32.
Where students go wrong
Using a slanted side as the height. Height always means the perpendicular distance, which on a parallelogram or trapezoid is not the same as the sloping edge.
Also called area formulas.
What you can put on this worksheet
Triangles
What is the area of the triangle? — a triangle with base 12 and height 5→ 30
Parallelograms
What is the area of the parallelogram? — a parallelogram with base 12 and height 5→ 60
Rectangles
What is the area of the rectangle? — a rectangle 12 by 5→ 60
Trapezoids
What is the area of the trapezoid? — a trapezoid with bases 8 and 4 and height 2→ 12
Rhombuses
Work out the area of this rhombus. — a rhombus with diagonals 10 and 12→ 60
Slanted bases, heights outside, extra sides, mixed units
Find the area of the shape. — a shape with a height of 3→ 42
Height outside, a base standing up, or a trapezoid upside down
Find the area of the parallelogram. — a parallelogram standing on a vertical side 5, with height 9 across→ 45
Questions about these worksheets
Yes. Every area of triangles and quadrilaterals sheet is free to print and free to download as a PDF. There is no account to make, no email to hand over and no limit on how many you take.
Yes. The answer key prints on a second page, and you can choose whether it shows each question beside its answer or just the answers in a list.
Yes. Print straight from the page, or download the PDF and print that. The sheet is laid out for paper rather than squeezed off a screen, so there is room to work under each question, and the answer key comes out on its own page.
Geometry is usually taken around 9th or 10th grade, though schools vary and plenty of students meet it earlier or later. Pick the difficulty rather than the grade: the easy level suits a first lesson on it, the hard level suits review before a test.
Yes, as many as you like. The questions are built fresh each time rather than picked from a fixed set of files, so pressing Generate gives a new sheet. That is what you want for a second class, a retake, or two students sitting next to each other.
That is the closest comparison, and Kuta Software is good software. It is also paid software you install on a computer. These worksheets run in a browser tab for free, with no account and nothing to install. Like Kuta, the area of triangles and quadrilaterals questions are generated when you ask for them rather than pulled from a fixed set of files, so two classes never get the same sheet, and the answer key comes with it.
Yes. There are three levels, and you can tick more than one for a sheet that mixes them, in which case the questions come out easiest first. The harder levels are not just larger numbers: they ask for something the easy ones do not.
You pick from 7: triangles, parallelograms, rectangles, trapezoids, rhombuses, slanted bases, heights outside, extra sides, mixed units and height outside, a base standing up, or a trapezoid upside down. Tick as many as you want and set how many of each, or let it spread them evenly.
Using a slanted side as the height. Height always means the perpendicular distance, which on a parallelogram or trapezoid is not the same as the sloping edge.