Grade 5 Geometry Worksheets — Triangle Area and Angles
Fifth grade is the year geometry starts to run backwards. Students still find the area of a rectangle, but now they also halve a base times a height for a triangle, and — the real step up — they are handed an area and asked for the side that produced it. Alongside that, angles on a straight line introduce the idea that angles in a figure add to a fixed total. Grade 5 offers seven separate sheets: Perimeter, Area of Rectangles, Area of Triangles, Naming Angles, Missing Angles, Coordinates and Volume of Cuboids.
Area of Triangles runs Base and height, then Extra measurements given, then Work backwards from the area. Missing Angles opens On a straight line and goes on to Around a point. Volume of Cuboids arrives this year. All seven draw. Perimeter, Area of Rectangles and Area of Triangles put the shape on the page with its measurements on the drawing rather than in the sentence — and on Area of Triangles that matters more than anywhere else, because a triangle’s height is not the length of any of its sides unless it is right-angled, so it is marked with a dashed line dropped from the point. Volume of Cuboids draws the box in three dimensions with its three edges measured. Coordinates prints a numbered grid beside every question and marks its points on it. Naming Angles and Missing Angles print the angles themselves, with their measurements on the drawing — and on Missing Angles that is the point of the card, because seeing whether the angles stand on a straight line or fill a whole turn is what tells a child to subtract from 180 or from 360. Grade 5's Naming Angles keeps its number on the figure for the opposite reason: half of its angles sit within ten degrees of a boundary, where 89° and 91° are the same picture and only the measurement separates them.
Build your worksheet
Geometry · Grade 5
The link is the save: it reopens this exact worksheet — same questions, same settings. Bookmark it or send it on. No account needed.
Printed on the worksheet only — never saved or sent anywhere
Live preview
Grade 5 · 4 pages · A4More Grade 5 geometry skills
Each one generates a different kind of question, with its own three levels and answer key.
- PerimeterAdd up every side to find the distance all the way around a shape.
- Area of RectanglesMultiply length by width to find the space a rectangle covers.
- Area of TrianglesMultiply the base by the height and halve it to find a triangle's area.
- Naming AnglesLook at a drawn angle and decide whether it is acute, right, obtuse, straight or reflex.
- Missing AnglesRead a drawn straight line or a full turn, and find the angle that is missing from it.
- CoordinatesRead, move and complete points on a printed coordinate grid.
- Volume of CuboidsFind how much space a box fills, in cubic centimeters.
What each level generates
Grade 5 perimeter — the exact skill behind each difficulty setting, straight from the generator.
- Level 1Rectangles
- Level 2Triangles and other polygons
- Level 3Find a missing side
Grade levels follow the progression common to most English-language curricula — not one specific national curriculum. Every level shows exactly what it generates, so you can check the fit with your own program. See the full scope & sequence →
Why the triangle formula is half a rectangle
Base × height ÷ 2 is easy to memorise and easy to misapply. The reason it works is worth two minutes: any triangle is exactly half of a rectangle built on the same base and the same height, so its area must be half. Students who have seen that once stop wondering whether to halve, and they stop reaching for a slanted side instead of the height. Extra measurements given is the level built for exactly that habit: it states a sloping side alongside the base and the height, and only two of the three numbers are wanted.
The measurements on these sheets are chosen so every triangle area lands on a whole number — one of the base or the height is always even. That is deliberate: at this stage a wrong answer should mean a wrong method, not a decimal that got rounded halfway through.
Working backwards from an area
Work backwards from the area is the level that separates recall from understanding. Given an area of 96 cm² and a length of 12 cm, a student who has understood area as a covering will divide; a student who has only memorised "length times width" often multiplies again. Encourage them to write the relationship first — 12 × ? = 96 — and then choose the operation. It is the same reasoning that solves an equation next year. Area of Rectangles carries its own version of that level, Find a side from the area.
The triangle version has one extra step and catches a lot of people: an area of 60 cm² with a base of 10 cm means the base times the height was 120, so the height is 12 cm, not 6 cm. Doubling before dividing is the habit to build here, and a short sheet of eight questions that all demand it is more useful than a long mixed one.
Frequently asked questions
▸How do you find the area of a triangle?
Multiply the base by the perpendicular height and halve the result. A triangle with a base of 14 cm and a height of 6 cm has an area of 14 × 6 ÷ 2 = 42 cm². Area of Triangles practises that on its Base and height level, with measurements chosen so answers stay whole; Area of Rectangles is the neighbouring sheet.
▸How do you find a missing side when you know the area?
Divide. If a rectangle has an area of 96 cm² and a length of 12 cm, the width is 96 ÷ 12 = 8 cm. For a triangle, double the area first: an area of 60 cm² on a base of 10 cm gives a height of 120 ÷ 10 = 12 cm. That reverse thinking is Find a side from the area on Area of Rectangles, and Work backwards from the area on Area of Triangles.
▸What do angles on a straight line add up to?
180°. The On a straight line level of Missing Angles states one of the angles and asks for the one that is missing, so students subtract from 180 rather than measuring. Around a point does the same against 360°. It is the groundwork for angle sums in a triangle the following year.
▸Are the answers always whole numbers?
Every answer is exact and nothing is rounded. On the Triangles and other polygons level of Perimeter the sides are measured to a tenth of a centimetre, so those totals carry one decimal place; every other Grade 5 answer is a whole number.