Questions I don't get (1 Viewer)

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The line is a tangent so its perpendicular distance from the centre of the the circle (the origin) is equal to the circle's radius.
 
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Alternatively, you could equate the two equations and note that the discriminant is zero and solve for r.
 

SpiralFlex

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Here you go.

scan0006.jpg

scan0007.jpg

To sum up,

1. Basically you use the distance perpendicular distance formula to confirm their distances equal.

Then you have x and y, but you still need z.

2. Find the x intercept (z) by letting y = 0

3. Use the distance formula to find the sides.

4. Then the cosine rule to find the angle

5. Finally use the area of the triangle formula, 1/2 (x*y*sin z)
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Note: It is a good idea to use a diagram to help you.
 
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MrBrightside

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Here you go.

View attachment 22598

View attachment 22599

To sum up,

1. Basically you use the distance perpendicular distance formula to confirm their distances equal.

Then you have x and y, but you still need z.

2. Find the x intercept (z) by letting y = 0

3. Use the distance formula to find the sides.

4. Then the cosine rule to find the angle

5. Finally use the area of the triangle formula, 1/2 (x*y*sin z)
______________________________________________________
Note: It is a good idea to use a diagram to help you.
hey thanks man, but for c, how did you get distance for XY. i got sqroot (-1-3)^2 + (0-2)^2 using then formula sqroot (x2 - x1)^2 + (y2 - y1)^2
 

SpiralFlex

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hey thanks man, but for c, how did you get distance for XY. i got sqroot (-1-3)^2 + (0-2)^2 using then formula sqroot (x1 - x2)^2 + (y2 - y1)^2
It is Sqrt of (-1-3)^2 + (0-2)^2

= 4

By the way, what textbook did you use for these questions?
 
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MrBrightside

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Wait, I think I did something wrong.
X is (3,2) Y is (-1,0) WHAT am i doing wrong ? :( i even tried urs in this thread its same thing as me, the one u did on sheet is different but i don't know how you got it. i'm using MIF.
 

SpiralFlex

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SORRY I GOT IT WRONG LOL! the sqrt 20 is right.

XY = SQRT 20

YZ = 5/4

XZ = (SQRT185)/4

I'll re-scan you working.
 

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