Year 2: Vertical lines of symmetry
Part of the Year 2 2-d and 3-d shapes chapter. Chapter overview · whole chapter on one page
Vertical lines of symmetry
A shape has a line of symmetry if you can fold it so that the two halves match.
In this chapter we look at a vertical line. It goes straight up and down through the middle.
A square has a vertical line of symmetry. A triangle standing up has one too.
A shape turned on its side may not fold up and down. Then it has no vertical line of symmetry.
Key ideas
- A line of symmetry folds a shape into two matching halves.
- A vertical line goes straight up and down.
- Turn a shape round in your head to check the fold.
- A sideways or slanting line is not a vertical line.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves do not match.Do the two halves match?
- Write the answer. No
Check. The shape is turned, so its line of symmetry slopes or goes sideways. A vertical fold does not match.
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Look for a straight up-and-down fold line where the two halves match.
- Look for a vertical fold line. Draw it straight up and down through the middle.one vertical line
- Check the fold. The two halves match, so the line is a line of symmetry.halves match
- Write the answer. 1
Check. There is only one vertical direction, so only one vertical line can be a line of symmetry. ✓
Watch out. A shape can have other lines of symmetry. Only the up-and-down line counts here.
Watch out
Watch out: a shape can have other lines of symmetry, which slope or go sideways. In this section we only look at the line that goes straight up and down.
Exam tip
Grown-up tip. Cut out a paper shape and fold it in half, straight up and down. If the two halves match, the fold is a vertical line of symmetry. Try the same shape turned on its side.
Exercise 8B Vertical lines of symmetry
Non-calculatorMethod. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves do not match.Do the two halves match?
- Write the answer. No
Check. The shape is turned, so its line of symmetry slopes or goes sideways. A vertical fold does not match.
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves do not match.Do the two halves match?
- Write the answer. No
Check. The shape is turned, so its line of symmetry slopes or goes sideways. A vertical fold does not match.
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves do not match.Do the two halves match?
- Write the answer. No
Check. The shape is turned, so its line of symmetry slopes or goes sideways. A vertical fold does not match.
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Check each shape for a vertical fold. Keep the ones where the halves match.
- Check shape A. The square folds up and down, and the halves match.A: yes
- Check shape B. The triangle is on its side, so the halves do not match.B: no
- Check shape C. The rectangle is tilted, so the halves do not match.C: no
- Check shape D. The oval folds up and down, and the halves match.D: yes
- Write the letters. A and D
Check. Each letter with a yes has halves that match along a vertical fold. ✓
Watch out. Turn the shape in your head. A turned shape often has a sideways fold.
Method. Imagine folding the shape in half, down the middle from top to bottom.
- Imagine a vertical fold. The fold line goes straight up and down.a straight up-and-down fold
- Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.Do the two halves match?
- Write the answer. Yes
Check. Trace one half, then the other. They are the same shape. ✓
Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.
Method. Look for a straight up-and-down fold line where the two halves match.
- Look for a vertical fold line. Draw it straight up and down through the middle.one vertical line
- Check the fold. The two halves match, so the line is a line of symmetry.halves match
- Write the answer. 1
Check. There is only one vertical direction, so only one vertical line can be a line of symmetry. ✓
Watch out. A shape can have other lines of symmetry. Only the up-and-down line counts here.
Method. Check a shape that is not a circle.
- Look at the square. The square folds up and down, and the halves match.square: yes
- Compare with Mia. The square is not a circle, but it has a vertical line of symmetry.not only circles
- Decide. Mia is not right.No
Check. A rectangle, an oval and a triangle standing up also have one. ✓
Watch out. Many shapes have a vertical line of symmetry, not only circles.