6. Find the area of the polygon PQRS with its vertices at P(1,-1), Q(6, -1), R(6,-6), and S(1, -6).
A. 50 square units
B. 12.5 square units
C. 20 square units
D.25 square units

Respuesta :

The area of the polygon PQRS is 25 square units ⇒ answer D

Step-by-step explanation:

Let us revise some important notes

  • The points lie on a horizontal line have same y-coordinates
  • The length of a horizontal distance is the difference between the x-coordinates of its end-points
  • The points lie on a vertical line have same x-coordinates
  • The length of a vertical segment is the difference between the y-coordinates of its end-points
  • If a horizontal line intersect a vertical line, then they formed a right angle at the point of intersection

The vertices of polygon PQRS are:

P = (1 , -1)

Q = (6 , -1)

R = (6 , -6)

S = (1 , -6)

∵ The polygon has 4 vertices

∴ The polygon PQRS is a quadrilateral

∵ y-coordinates of points P and Q are equal

∴ PQ is a horizontal side

∵ The length of PQ = [tex]x_{Q}-x_{P}[/tex]

∵ [tex]x_{Q}=6[/tex] and [tex]x_{P}=1[/tex]

∴ PQ = 6 - 1 = 5 units

∵ x-coordinates of points Q and R are equal

∴ QR is a vertical side

∵ The length of QR = [tex]y_{Q}-y_{R}[/tex]

∵ [tex]y_{Q}=-1[/tex] and [tex]y_{R}=-6[/tex]

∴ QR = -1 - (-6) = -1 + 6 = 5 units

∵ y-coordinates of points R and S are equal

∴ RS is a horizontal side

∵ The length of RS = [tex]x_{R}-x_{S}[/tex]

∵ [tex]x_{R}=6[/tex] and [tex]x_{S}=1[/tex]

∴ RS = 6 - 1 = 5 units

∵ x-coordinates of points S and P are equal

∴ SP is a vertical side

∵ The length of SP = [tex]y_{P}-y_{S}[/tex]

∵ [tex]y_{P}=-1[/tex] and [tex]y_{S}=-6[/tex]

∴ SP = -1 - (-6) = -1 + 6 = 5 units

In the quadrilateral PQRS

∵ PQ and SR are horizontal lines

∵ PQ // SR

∵ QR and SP are vertical lines

∴ QR // SP

∵ Each horizontal line ⊥ to each vertical line

∴ Each two adjacent sides are ⊥

∴ PQ ⊥ QR , QR ⊥ RS , RS ⊥ SP , SP ⊥ PQ

∴ m∠P = 90° , m∠Q = 90° , m∠R = 90° , m∠S = 90°

∵ PQ = QR RS = SP = 5 units

∵ Each two opposite sides are parallel

∵ All sides are equal in length

∵ All angles are right angles

∴ The quadrilateral PQRS is a square of side length 5 units

∵ Area of square = (side)²

∵ The length of the side is 5 units

∴ Area of square PQRS = (5)² = 25 units²

The area of the polygon PQRS is 25 square units

Learn more:

You can learn more about area of shapes in brainly.com/question/6837543

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