Perimeter and area of shapes on the coordinate plane
Grade 10 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.
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Use this
Proof: 1. Slope AB = 3/4 = slope DC, and slope BC = -4/3 = slope AD. 2. Opposite sides are parallel, so ABCD is a parallelogram. 3. ? 4. So ABCD is a rectangle.
Luz is writing a coordinate proof that this is a rectangle. One step is missing. Which statement belongs in the blank?
- (3/4)(-4/3) = -1, so AB ⊥ BC
- Slope AB = slope DC, and slope BC = slope AD
- AB ≠ BC, so ABCD is not a rhombus
- Slope AB = slope BC, so ABCD has a right angle
Use this
Proof: 1. The midpoint of AC is (0, 0), and so is the midpoint of BD. 2. The diagonals bisect each other, so ABCD is a parallelogram. 3. ? 4. So ABCD is a rhombus.
Milo is writing a coordinate proof that this is a rhombus. One step is missing. Which statement belongs in the blank?
Quadrilateral ABCD with A(-6, 0), B(0, 8), C(6, 0), D(0, -8). Proof: 1. The midpoint of AC is (0, 0), and so is the midpoint of BD. 2. The diagonals bisect each other, so ABCD is a parallelogram. 3. ? 4. So ABCD is a rhombus. Quadrilateral ABCD with A(-6, 0), B(0, 8), C(6, 0), D(0, -8). Proof: 1. The midpoint of AC is (0, 0), and so is the midpoint of BD. 2. The diagonals bisect each other, so ABCD is a parallelogram. 3. ? 4. So ABCD is a rhombus. A(-6, 0) B(0, 8) C(6, 0) D(0, -8) - AB = BC = 10
- ∠A = ∠C, because opposite angles of a parallelogram are equal
- AC = BD, since both diagonals have the same length
- Slope AB = slope DC, since both are 4/3
Noah is writing a coordinate proof that this is a right triangle. One step is missing. Which statement belongs in the blank?
Triangle ABC with A(-2, -1), B(2, 2), C(5, -2). Proof: 1. AB = 5 and BC = 5. 2. AC = √50. 3. ? 4. So the angle at B is a right angle. Triangle ABC with A(-2, -1), B(2, 2), C(5, -2). Proof: 1. AB = 5 and BC = 5. 2. AC = √50. 3. ? 4. So the angle at B is a right angle. −4 −3 −2 1 2 3 4 5 6 7 −4 −3 −2 −1 1 2 3 4 AB = 5 BC = 5 AC = √50 A B C Proof: 1. AB = 5 and BC = 5. 2. AC = √50. 3. ? 4. So the angle at B is a right angle. - AB = BC, so the triangle is isosceles
- AC = √50, the longest side
- AB² + BC² = 25 + 25 = 50 = AC²
- AB + BC = AC
Use this
Quadrilateral ABCD with A(-5, -1), B(1, -1), C(5, 3), D(-1, 3). Proof: 1. The midpoint of AC is (0, 1). 2. ? 3. The diagonals bisect each other. 4. So ABCD is a parallelogram.
Pia is writing a coordinate proof that this is a parallelogram. One step is missing. Which statement belongs in the blank?
- The midpoint of AB is (-2, -1)
- The midpoint of BD is (0, 1), the same point
- The midpoint of AC is (0, 1)
- AC = BD, since both diagonals have the same length
Ren says ABCD is a square because AB = BC = CD = DA = 5. Which reply finds the error?
Quadrilateral ABCD with A(-4, 0), B(0, 3), C(4, 0), D(0, -3). Quadrilateral ABCD with A(-4, 0), B(0, 3), C(4, 0), D(0, -3). x y -4 4 3 -3 A(-4, 0) B(0, 3) C(4, 0) D(0, -3) - Nothing: a quadrilateral with four equal sides is a square, because a square is defined by its sides alone
- AB and DC have different slopes, so ABCD is not even a parallelogram, and the proof fails at that step
- AB is not 5: the run is 4 and the rise is 3, so AB = 7, and the four sides are not equal after all
- Equal sides prove a rhombus. A square also needs a right angle, and AB and BC have slopes 3/4 and -3/4, which do not multiply to -1
Tala says ABCD is a rectangle because AB = DC and AD = BC. Which reply finds the error?
Quadrilateral ABCD with A(-4, -2), B(1, -1), C(4, 3), D(-1, 2). Quadrilateral ABCD with A(-4, -2), B(1, -1), C(4, 3), D(-1, 2). x y A(-4, -2) B(1, -1) C(4, 3) D(-1, 2) - AB and DC are not parallel, so ABCD is not even a parallelogram, and the proof fails at that step
- Nothing: opposite sides that are equal make a rectangle, because both pairs of opposite sides match in length
- AD is not 5: the run is 3 and the rise is 4, so AD = 7, and the opposite sides are not equal after all
- Opposite sides equal prove a parallelogram. A rectangle also needs a right angle, and AB and AD have slopes 1/5 and 4/3, which do not multiply to -1
Zee says triangle ABC has a right angle at B because AB = BC. Which reply finds the error?
Triangle ABC with A(1, -2), B(4, 2), C(7, -2). Triangle ABC with A(1, -2), B(4, 2), C(7, -2). −1 1 2 3 4 5 6 7 8 9 −4 −3 −2 −1 1 2 3 4 0 A B C - Nothing: two equal sides next to B make the angle at B a right angle, since the triangle looks square at B
- AC is not 6: the run is 6 and the rise is 0, so AC = 36, and the triangle is not isosceles
- Equal sides prove an isosceles triangle. A right angle at B needs AB² + BC² = AC², but 25 + 25 = 50 and AC² = 36
- AB is not equal to BC, so even the first fact is wrong, and the whole claim falls apart there
Ari says the point P with AP:PB = 2:3 is 2/3 of the way from A(-6, 2) to B(9, -3). Which reply finds the error?
Segment AB from A(-6, 2) to B(9, -3). Segment AB from A(-6, 2) to B(9, -3). −8 −6 −4 −2 4 6 8 10 −4 −2 2 4 0 A B - B - A is not (15, -5): the run is 3 and the rise is 1, so P is not 2/3 of the way
- A and B are in the wrong order, so P must be measured from B and not from A
- AP:PB = 2:3 puts P 2 of 5 equal parts from A, which is 2/5 of the way, not 2/3
- Nothing: the first number in the ratio is the fraction of the way, so 2:3 means 2/3 of AB
Bo's park route runs from A(-7, -3) to B(3, 7). Point P is on AB with AP:PB = 3:2. Where is P? Write it like (7, -3).
Coordinate grid, each square 1 unit on a side; both axes run from negative ten to ten. Segment AB from A(-7, -3) to B(3, 7); P is not drawn. Coordinate grid, each square 1 unit on a side; both axes run from negative ten to ten. Segment AB from A(-7, -3) to B(3, 7); P is not drawn. −10 −8 −6 −4 −2 2 4 6 8 10 −10 −9 −8 −7 −6 −5 −4 −3 −2 −1 1 2 3 4 5 6 7 8 9 10 A B P is not drawn. Esme's rug route runs from A(-8, 4) to B(4, -4). Point P is on AB with BP:PA = 1:3. Where is P? Write it like (7, -3).
Coordinate grid, each square 1 unit on a side; both axes run from negative ten to ten. Segment AB from A(-8, 4) to B(4, -4); P is not drawn. Coordinate grid, each square 1 unit on a side; both axes run from negative ten to ten. Segment AB from A(-8, 4) to B(4, -4); P is not drawn. −10 −8 −6 −4 −2 2 4 6 8 10 −10 −9 −8 −7 −6 −5 −4 −3 −2 −1 1 2 3 4 5 6 7 8 9 10 A B P is not drawn.