Finding the area of a triangle on a graph

[Count Duckula]

Here is the question: http://i259.photobucket.com/albums/hh299/the-real-guitar-hero/Capture_zpsf2b9cd28.png

part A = 3√5
b=y=2X+1
c=(0,1)
D is where I am confused. Area of triangle = (base x height)/2
from working out, line 2 cuts the x-axis at -1/2. line 1 cuts the x at 7. the height is 3. thus the area should be [(7.5*3)/2] = 11.25 . but the mark scheme says the answer is 7.5? which is length of the base! but the heck?This is just one of those small things that has confused the hell out of me >.<

 

[CompuChip]

The base of the triangle is PR, which does not have length 7 because P is not on the x-axis!
Similarly, the height of the triangle is PQ.

 

[Count Duckula]

Ugh. ok, so its, 3√5 * √5

 

[CompuChip]

Almost :)

Area of triangle = (base x height)/2

 

[CellCoree]

I understand your confusion and frustration. It seems that the mark scheme may have made a mistake or misinterpretation. The formula for finding the area of a triangle is indeed (base x height)/2, and based on your calculations, the base should be 7.5 and the height should be 3. Therefore, the area of the triangle should be (7.5 x 3)/2 = 11.25, not 7.5 as stated in the mark scheme.

It is possible that there was a typo or error in the mark scheme, or the person grading the question may have misunderstood the problem. It is important to always double-check and verify answers, especially in science where accuracy is crucial.

In addition, it is always helpful to show your work and explain your reasoning when solving problems. This can help identify any mistakes and also demonstrate your understanding of the concept.

I hope this helps clarify the confusion and I encourage you to continue questioning and seeking clarification when things don't seem to add up. This is an important skill for any scientist.