Question

A quadrilateral with vertices (-3,2),(-5,-4), (4,6), and (7,0) is dilated by a scale factor of 0.5.
Which matrix represents the quadrilateral after it has been dilated?
A.) 1.5 2.5 -2 -3.5
-1 2 -3 0
B.) -1.5 -2.5 2 3.5
1 -2 3 0
C.) -4.5 -7.5 6 10.5
3 -3 9 0
D.) -3.5 -5.5 4.5 7. 5
2.5 -4.5 6.5 0.5

Answer 1

Original vertices:
1 (-3, 2)
2 (-5,-4)
3 ( 4, 6)
4 ( 7, 0)

dilated by a scale factor of 0.50

1) -3*0.50 = -1.5 ; 2 * 0.50 = 1 ⇒ (-1.5,1)
2) -5*0.50 = -2.5 ; -4*0.50 = -2 ⇒(-2.5,-2)
3) 4*0.50 = 2; 6*0.50 = 3 ⇒ (2,3)
4) 7*0.50 = 3.5; 0*0.50 = 0 ⇒ (3.5,0)

B.)
 -1.5    -2.5    2    3.5 
     1       -2    3       0