Using the y=mx+c, find how tall a player will be if they get 3 rebounds.
Pictures :
http://imgur.com/a/24Wbn
DATA IS AS FOLLOWS.
198, 9
187, 2
201, 13
184, 3
204, 4
179, 2
210, 18
185,3
202,11
196,7
205,15
189,16
Data in table continues, the 2 tables are one, just split due to size limits.
X Values range from 179 - 210 ( on data table)
Y values range from 0 - 18 ( on data table)
When i try to work this problem out, i pick two points to find the gradient, in this case:
(182, 4) AND (203,12)
Then use formula to figure out graident:
M=Y2-Y1 OVER X2-X1
= 12-4 OVER 203-185 = 0.4444
M= 0.4444
Then i find Y intercept, using algabra ( teacher said to )
I choose one coord, then sub values into equation.
(185,4)
4=0.4444 X 185 + C
4=82.214 + C
4-82.214= C
C= -78.214
Equation is Y=0.4444X - -78.214
So i then do:
Y=0.4444 X 3 - -78.214
= 79.5472
But on my line of best fit, it should be 183 in height, not 79. What have i done wrong? i am so confused! Thank you for your time
Unless i have entered the values wrongly, Excel shows me that for 3 rebounds the expected height is approx 188.5cm
If i use the regression formula that Excel gave me
y=0.4063x-70.647
$${\mathtt{3}} = {\mathtt{0.406\: \!3}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{70.647}} \Rightarrow {\mathtt{x}} = {\frac{{\mathtt{736\,470}}}{{\mathtt{4\,063}}}} \Rightarrow {\mathtt{x}} = {\mathtt{181.262\: \!613\: \!832\: \!143\: \!736\: \!2}}$$
It can't be 79, no one in the sample is that short :))
Unless i have entered the values wrongly, Excel shows me that for 3 rebounds the expected height is approx 188.5cm
If i use the regression formula that Excel gave me
y=0.4063x-70.647
$${\mathtt{3}} = {\mathtt{0.406\: \!3}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,-\,}}{\mathtt{70.647}} \Rightarrow {\mathtt{x}} = {\frac{{\mathtt{736\,470}}}{{\mathtt{4\,063}}}} \Rightarrow {\mathtt{x}} = {\mathtt{181.262\: \!613\: \!832\: \!143\: \!736\: \!2}}$$
It can't be 79, no one in the sample is that short :))