WILL FAN AND MEDAL! help??

Question

rz172 · Answer

attachment

rz172 · Answer

Could the answer be "y=mx+b"? So "m" would be the answer? M = 1 because slope is 9 / 9. "b" means the y intersect. But I don't know what would go in there?

harman.singh · Answer

Your answer for 'm' is correct. 

To find the b.
use the equation y=mx+b
Sub in the value for m, y & x, then solve for b

rz172 · Answer

But i need the answer for the green part in "?" which is before the x.. Is it 9/9 or 1?

harman.singh · Answer

It would be 1

harman.singh · Answer

9/9 = 1

rz172 · Answer

Okay now this part of the same question :

harman.singh · Answer

You should always aim to write the answer in most simplified form possible, unless specified.

harman.singh · Answer

Are you referring to the second question or the first one?

harman.singh · Answer

No, 9 would be incorrect. Could you please tell me what values of x & y did you use?

harman.singh · Answer

Oh, I see where you went wrong. You are subbing in wrong sets of coordinates.

These are the two sets of (x,y) coordinates:
(7,20)
(-2,11)

To find the b value you can pick any of the two sets of coordinates and substitute them into the equation.
Lets pick (7,20)
So now, 
your x value = 7
y value = 20

Can you find the 'b' value from here and show me what you get?

Equation: y=mx+b

harman.singh · Answer

So, here is the equation for a straight line:

y=mx+b

Lets rearrange this equation to get 'b' on its own
b=y-mx

So. to find the value for b, we need to sub in the values for 'y' , 'm' & 'x'.

With me so far?

rz172 · Answer

No.. i'm still clueless.n can i have an example?

harman.singh · Answer

Yea sure.

Lets say we are given a gradient of a line:
m = 2

We are also given a set of coordinate in the form of (x,y) which is:
(4,10)

And we are asked to find the 'b' value.

I will start by writing out the equation and getting b on one side of the equation
$$y=mx+b$$
$$b=y-mx$$

Now that I have my equation rearranged, I can simply sub in my values for m, x, & y to find 'b'.
In this example, x=4,     y=10,    m=2

So after subbing in the values, I get:
$$b=10-(2*8)$$
Therefore, $$b=2$$ 
and that's all we needed to solve.

Do you understand this procedure?

rz172 · Answer

If I do it the same way would the answer be 13 for mine?

harman.singh · Answer

Correct :)