Deductive reasoning
![](https://dmn92m25mtw4z.cloudfront.net/img_set/sprite/v1/sprite-1w.png)
Get the most by viewing this topic in your current grade. Pick your course now.
Intros
Examples
Lessons
- Using the Law of Detachment
You are given the statements below. Assume these statements are true. Determine if a conclusion can be made by using the Law of Detachment. - Given the information and a statement below, determine if the conclusion is valid. Explain why it is valid or invalid.
If two lines are perpendicular, then they intersect - Using the Law of Syllogism
You are given the statements below. Assume these statements are true. Determine if a conclusion can be made by using the Law of Syllogism.- If the measure of an angle is 90°, then it is a right angle.
If it is a right angle, then it is not obtuse. - If you drive a car, then you can get to the grocery store in 30 minutes
If you get to the grocery store in 30 minutes, then you will get home on time - If you drink coffee, then you will stay awake
If you stay awake, then you drink coffee.
- If the measure of an angle is 90°, then it is a right angle.
- Given the information below, determine if the conclusion is valid. Explain why it is valid or invalid.
- Given: If the shape is a square, then it is a regular polygon.
If it is a regular polygon, then all sides are equal.
Conclusion: If the shape is a square, then all sides are equal. - Given: If the shape is a square, then it is a regular polygon.
If it is a regular polygon, then all sides are equal.
Conclusion: If all sides are equal, then the shape is a square.
- Given: If the shape is a square, then it is a regular polygon.