Using Slopes of Parallel Lines Quick Check
Item 1
A quadrilateral ABCD has vertices A at (0,2), B at (2,6), C at (9,6), and D at (7,2). Are the opposite sides of this
quadrilateral parallel? (1 point)
Item 2
O Yes. AB is parallel to CD, but AD is not parallel to BC
Item 3
Item 4
O Yes. AB is parallel to CD and AD is parallel to BC
Item 5
O NO AD is parallel to BC but AB is not parallel to CD
O NO AB is parallel to CD, and AD is parallel to BC

Respuesta :

Answer:

The answer is (B)Yes. AB is parallel to CD and AD is parallel to BC

Step-by-step explanation:

There is an important fact about the parallel lines:

  • Parallel lines have equal slopes

The rule of the slope of a line is:

  • [tex]m=\frac{y_{2}-y_{1} }{x_{2}-x_{1}}[/tex], where [tex](x_{1},y_{1})[/tex] and [tex](x_{2},y_{2})[/tex] are two points on the line

Let us use the fact and the rule to solve the question

∵ ABCD is a quadrilateral

∵ A = (0, 2) , B = (2, 6), C = (9, 6), D = (7, 2)

∵ The opposite sides are AB, CD and AD, BC

Find the slopes of the four sides to check the parallel sides

∵ [tex]m_{AB}=\frac{6-2}{2-0}=\frac{4}{2}=2[/tex]

∵ [tex]m_{CD}=\frac{2-6}{7-9}=\frac{-4}{-2}=2[/tex]

∵ The slope of AB = The slope of CD

AB // CD

∵ [tex]m_{AD}=\frac{2-2}{7-0}=\frac{0}{7}=0[/tex]

∵ [tex]m_{BC}=\frac{6-6}{9-2}=\frac{0}{7}=0[/tex]

∵ The slope of AB = The slope of CD

AD // BC

The correct answer is:

Yes. AB is parallel to CD and AD is parallel to BC ⇒ (B)