+502 http://papers.xtremepapers.com/CIE/Cambridge%20IGCSE/Mathematics%20(0580)/0580_s11_qp_22.pdf
Help me in question number 18
+118608 Let see
A(7,0) B(5,3)
Midpoint of AB = \((\frac{7+5}{2},\frac{0+3}{2})=(6,1.5)\)
equation of CB
The y intersept is 4 b=4
Draw in the right angled triangle between the points B and C and you can see the gradient m
i.e.
\(m=\frac{rise}{run}=\frac{-1}{5}\)
so the equation of BC is
\(y=\frac{-1}{5}x+4\\ y=\frac{-x}{5}+4\\\)
+118608 The midpint is just (the average of the 2 x values, the average of the 2 y values)
To get the average of 2 numbers you add them together and divide by 2
So the average of 12 and 5 for instance is (12+5)/2 = 17/2 = 8.5
If you want the more formal look,
The mid point of
\((x_1,y_1)\;\;and\;\;(x_2,y_2) \;\;is\;\;\;\;(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})\)
The y intercept is where the line crosses the y axis and you can see that it crosses at 4
SO the y intercept, which is always given the letter b =4
