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# exponential graphs Watch

1. how to finds coordinates when two exponential graphs insect?

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2. You know that at the point of intersection, that both the x and y values must be the same. So y = y - can you see where to go from here (it's the same process as finding the intersection between a straight line y = mx + c and a quadratic y = ax^2 + bx + c)?
3. (Original post by tory88)
You know that at the point of intersection, that both the x and y values must be the same. So y = y - can you see where to go from here (it's the same process as finding the intersection between a straight line y = mx + c and a quadratic y = ax^2 + bx + c)?
thanks for trying to help but I've labelled the graphs wrong. the n and m should swap over. And I don't really understand what you mean.
4. (Original post by Purple27)
thanks for trying to help but I've labelled the graphs wrong. the n and m should swap over. And I don't really understand what you mean.
Would you know how to find the point of intersection of two straight lines?
5. (Original post by tory88)
Would you know how to find the point of intersection of two straight lines?
yh you can find out using simultaneous equations
6. (Original post by Purple27)
yh you can find out using simultaneous equations
So if I had two lines:

(1) y = 2x
(2) y = x + 6

How would you find their point of intersection?
7. (Original post by tory88)
So if I had two lines:

(1) y = 2x
(2) y = x + 6

How would you find their point of intersection?
by moving the x to the other side

x= 6 y=12
8. (Original post by Purple27)
by moving the x to the other side

x= 6 y=12
Well, another way to d this is to say that at the point of intersection, both lines much have the same co-ordinates (otherwise they aren't intersecting). And so you can say that:

y1 = y2

Where y1 is the y value of the first equation and y2 the equation of the second one. And so replace each y with the other half of its equation:

2x = x + 6
x = 6

As you found. Subbing x = 6 into y = 2x then gives the full co=ordinates of the point of intersection (6,12).

So, using this method, can you see how you could find the points of intersection for your curves?
9. (Original post by tory88)
Well, another way to d this is to say that at the point of intersection, both lines much have the same co-ordinates (otherwise they aren't intersecting). And so you can say that:

y1 = y2

Where y1 is the y value of the first equation and y2 the equation of the second one. And so replace each y with the other half of its equation:

2x = x + 6
x = 6

As you found. Subbing x = 6 into y = 2x then gives the full co=ordinates of the point of intersection (6,12).

So, using this method, can you see how you could find the points of intersection for your curves?
Yh, but the questions I have x as a power. Am not really good with powers
10. (Original post by Purple27)
Yh, but the questions I have x as a power. Am not really good with powers
OK, so go as far as you can and post where you get stuck.

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