The points A(5, -4) and C(11, 6) are such that AC is the diagonal of a square, ABCD.
- (a)Find the length of the line AC.[2]
- (b)(i)The coordinates of the centre, E, of the square are (8, y). Find the value of y.[1]
- (b)(ii)Find the equation of the diagonal BD.[3]
- (b)(iii)Given that the x-coordinate of B is less than the x-coordinate of D, write EB and ED as column vectors.[2]
Mark scheme
Marking points from the official mark scheme (May/June 2021). The mark or mark type is shown in brackets.
- (a) M1 √(11-5)² + (6--4)² oe
- (a) A1 11.7 or 11.66[19...] rot to 4 or more figs
- (b)(i) B1 [y= ] 1
- (b)(ii) B1 m_AC = (6--4)/(11-5) or 10/6 nfww oe
- (b)(ii) M1 m_BD = -1 / (their 10/6) oe
- (b)(ii) A1 FT their 1 from (b)(i) and their perpendicular gradient y - their 1 = -3/5 (x-8) oe isw
- (b)(iii) B2 B1 for either (-5, 3) and (5, -3)
- (b)(iii) If 0 scored, SC1 for –5i + 3j and 5i -3j
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →