Q1. Which symbol ensures the area is always positive?
✔ Modulus bars convert negative results to positive values.
Q2. Find area for vertices (0,0), (4,0), (0,3).
✔ Base is 4, height is 3, Area = 0.5 * 4 * 3 = 6.
Q3. What happens if you swap x and y coordinates?
✔ Swapping coordinates changes the shape and calculated area value.
Show transcript
[Slide 1] Visualizing the Area
Welcome students. We know area is half base times height. But in coordinate geometry, finding height is tricky. Let's use a direct formula instead.
[Slide 2] Coordinate Geometry Formula
Here is the master formula. Take coordinates of three vertices. Plug them into this expression and take the absolute value. This gives exact area without drawing height.
[Slide 3] Solving a Problem
Let's try vertices A one two, B four six, and C six two. Substitute these numbers into our formula step by step. Simplify the brackets first to avoid errors.
[Slide 4] Watch Out for Errors
Students often forget the modulus bars. Area cannot be negative, so always take absolute value. Also ensure x and y pairs stay together during substitution.
[Slide 5] Key Takeaways
Remember this formula saves time in exams. Check your signs and modulus bars carefully. Practice more questions to master coordinate geometry.