OCR MEI C1 2012 January — Question 10 11 marks

Exam BoardOCR MEI
ModuleC1 (Core Mathematics 1)
Year2012
SessionJanuary
Marks11
PaperDownload PDF ↗
TopicStraight Lines & Coordinate Geometry
TypeEquation of line through two points
DifficultyModerate -0.3 This is a multi-part coordinate geometry question requiring standard techniques (gradient, equation of line, perpendicularity check, area, midpoint) but with minimal problem-solving demand. Part (iii)'s insight about equidistance is accessible once you recognize D is the midpoint of the hypotenuse in a right-angled triangle. Slightly easier than average due to routine methods and straightforward calculations.
Spec1.03a Straight lines: equation forms y=mx+c, ax+by+c=01.03b Straight lines: parallel and perpendicular relationships

10 Point A has coordinates (4, 7) and point B has coordinates (2, 1).
  1. Find the equation of the line through A and B .
  2. Point C has coordinates ( \(- 1,2\) ). Show that angle \(\mathrm { ABC } = 90 ^ { \circ }\) and calculate the area of triangle ABC .
  3. Find the coordinates of D , the midpoint of AC . Explain also how you can tell, without having to work it out, that \(\mathrm { A } , \mathrm { B }\) and C are all the same distance from D.

10 Point A has coordinates (4, 7) and point B has coordinates (2, 1).\\
(i) Find the equation of the line through A and B .\\
(ii) Point C has coordinates ( $- 1,2$ ). Show that angle $\mathrm { ABC } = 90 ^ { \circ }$ and calculate the area of triangle ABC .\\
(iii) Find the coordinates of D , the midpoint of AC .

Explain also how you can tell, without having to work it out, that $\mathrm { A } , \mathrm { B }$ and C are all the same distance from D.

\hfill \mbox{\textit{OCR MEI C1 2012 Q10 [11]}}