Question 1
Question: If the distance between the points (5, -6) and (x, -1) is 13, find the positive values of x. [3 Mark]
Answer: The distance between two points is given by ![]()
Given A (5, -6), B (x, -1), AB = 13
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Squaring both the sides,
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Solving this quadratic equation,
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Given x is a positive value, hence x = 17.
Question 2
Question: Show that the point A (7, 7) is equidistant from the points B (3, 4) and C (4, 3). [3 Mark]
Answer: Given, A (7, 7) is equidistant from B (3, 4) and C (4, 3)![]()
Hence AB is given by distance formula, ![]()
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= 5 units
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= 5 units
Hence AB = AC
Question 3
Question: Calculate the distance between the points P(3, 5), Q(6, 7). Leave your answer in root form. [2 Mark]
Answer: ![]()
A(x1, y1), B(x2, y2) distance between AB by distance formula is,
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Question 4
Question: Calculate the distance between the points (-3, 5) and (4, -6), leave your answer in surd form. [2 Mark]
Answer: Let A(-3, 5) and B(4, -6)
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Question 5
Question: Prove that the points A(-5, 4), B(-1, -2) and C(5, 2) are the vertices of an isosceles right angled triangle. [3 Mark]
Answer: Given that ABC is a triangle.

If ABC is an isosceles D le, then AB = BC.
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Hence ABC is an isosceles triangle.
If it is a right angled triangle then,
AC2 = AB2 + BC2
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AC2 = 104 units
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= 2 x 52
= 104 units
Hence AC2 = AB2 + BC2 and AB = BC
is an isosceles right angled triangle.
Question 6
Question: Prove that the points (3, 1), (4, 3), (0, 3) and (-1, 1) are the vertices of a parallelogram. Or diagonals bisect each other. [3 Mark]
| Hint: |
| Show that the opposite sides are equal |
Hint:Show that the opposite sides are equal
Answer: 
Let A(3, 1), B(4, 3), C(0, 3), D(-1, 1) the vertices of a (parallelogram) Quadrilateral.
In a parallelogram opposite sides are equal and parallel.
Hence if AB = CD and AD = BC, then ABCD is a parallelogram.
By distance formula,
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Hence one pair of opposite sides are equal.
Consider AD and BC,
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= 4 units
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= 4 units
Hence AB = DC and AD = BC
ABCD is a parallelogram.
Question 7
Question: Prove that the triangle PQR with vertices P (5, -3), Q (5, 0), R (2, 0) is an isosceles triangle. [2 Mark]
Answer: 
If triangle PQR is an isosceles triangle then either PQ = QR,
(or any 2 sides are equal)
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PQ ![]()
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= 3 units
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PQ = QR Hence
is isosceles.
Question 8
Question: Find the Co-ordinates of the points whose abscissa is 10 and which are at a distance of 10 units from (2, -3). [3 Mark]
Answer: Let the point A whose abscissa is 10 have the co-ordinates as A (10, y).
Another point B (2, -3)
AB = 10 units (given)
According to distance formula,
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Squaring both the sides,
100 = y2 + 6y + 73
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Solving the quadratic,
y2 + 6y - 27 = 0
y2 + 9y - 3y - 27 = 0
y(y + 9) - 3(y + 9) = 0
(y + 9(y - 3) = 0
y = -9 or y = 3
Vertices of ordinates are -9 or 3
Points are, (10, -9) or (10, 3)
Question 9
Question: Prove that A (-4, 3), B (0, 9), C (-3, 11) and D (-7, 5) form a parallelogram ABCD. [3 Mark]
Answer: If ABCD are the vertices of the parallelogram, then their opposite sides are equal in length and parallel.
AB = CD and BC = AD
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Hence AB = CD
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Hence BC = AD
ABCD is a parallelogram.
Question 10
Question: Prove that P (-5, 4), Q (-1, -2), R (5, 2) and S (1, 8) form a square PQRS. [3 Mark]
Answer:

According to the property of square, if PQRS is a square then all the sides are equal
PR = QS
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Hence PQ = QR = RS = SP.
All the sides are equal.
One of the diagonals,
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Hence PR = SQ
Diagonals are equal.
Hence PQRS is a square.
