### Junior Cert Ordinary Constructions

The **Junior Cert Ordinary **course contains 13 geometry constructions.

Geometry constructions have been examined almost every year in the Junior Cert Ordinary exam. If you are aiming for a high grade, you can’t afford to neglect this part of the course.

For general guidance on how to learn and revise constructions, click **here**.

Here’s the full list of JCO constructions, and the demo videos are embedded below this.

Construction 1 – Bisector of an angle, using only compass and straight edge

Construction 2 – Perpendicular bisector of a segment, using only compass and straight edge

Construction 4 – Line perpendicular to a given line l, passing through a given point on l

Construction 5 – Line parallel to given line, through a given point

Construction 6 – Division of a line segment into 2, or 3 equal segments without measuring it

Construction 8 – Line segment of a given length on a given ray

Construction 9 – Angle of a given number of degrees with a given ray as one arm

Construction 10 – Triangle, given lengths of 3 sides

Construction 11 – Triangle, given SAS data

Construction 12 – Triangle, given ASA data

Construction 13 – Right-angled triangle, given length of hypotenuse and one other side

Construction 14 – Right-angled triangle, given one side and one of the acute angles

Construction 15 – Rectangle given side lengths

**See below for our demonstration videos showing you exactly how to do them.**

If you need any further help or clarification, **get in touch** with us at any time!

#### All 13 Constructions for Junior Cert Ordinary Level

**Full Playlist** – all 13 videos on our YouTube channel

**Construction** **1** – Bisector of an angle, using only compass and straight edge

**Construction** **2** – Perpendicular bisector of a segment, using only compass and straight edge

**Construction 4 **– Line perpendicular to a given line l, passing through a given point on l

**Construction** **5 **– Line parallel to given line, through a given point

**Construction** **6** and **7 **– Division of a line into 2, 3 or any number of equal segments without measuring it [7 Not on Ordinary Level]

**Construction** **8 **– Line segment of a given length on a given ray

**Construction** **9** – Angle of a given number of degrees with a given ray as one arm

**Construction** **10** – Triangle, given lengths of 3 sides

**Construction** **11** – Triangle, given SAS data

**Construction** **12** – Triangle, given ASA data

**Construction** **13** – Right-angled triangle, given length of hypotenuse and one other side

**Construction** **14** – Right-angled triangle, given one side and one of the acute angles

**Construction** **15** – Rectangle given side lengths

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