Answer:
-6/8
Step-by-step explanation:
The rate of change is the same as the slope (I don't know if you have learned that term yet), but basically its the change in y's over the change in x's. to find this out, all you have to do is count from the point on the graph that is the farthest right (in this case, (6,1)), up to the y coordinate of the point farthest to the left (-2, 7) which is 6, and then count the number of spaces between the x coordinates, which is 8. put the rise (up and down count) over the run (horizontal count) in a fraction form, which gives you 6/8, and then notice how the line is pointing towards the bottom RIGHT hand corner making the line negative, so you need to make the rate of change negative, giving you the final answer of -6/8.
Answer:
2
Step-by-step explanation:
Answer:
The Law of Cosine : cos C = 
Step-by-step explanation:
See the figure to understand the proof :
Let A Triangle ABC with sides a,b,c,
Draw a perpendicular on base AC of height H meet at point D
Divide base length b as AD = x -b and CD = x
By Pythagoras Theorem
In Triangle BDC And In Triangle BDA
a² = h² + x² ( 1 ) c² = h² + (x-b)²
c² = h² + x² + b² - 2xb ...(. 2)
From above eq 1 and 2
c² = (a² - x²) + x² + b² - 2xb
or, c² = a² + b² - 2xb .....(3)
Again in ΔBDC
cos C = 
Or, cos C = 
∴ x= a cos C
Now put ht value of x in eq 3
I.e, c² = a² + b² - 2ab cos C
Hence , cos C = Proved Answer
