Answer:
B)-4
Step-by-step explanation:
We are given that in a figure
The vertices of small triangle are (1,1),(-1,-1) and (1,-1).
The vertices of big triangle are (1,-9) ,(9,-1) and (1,-1).
Side of small triangle=[tex]\sqrt{(-1-1)^2+(-1-1)^2}=2[/tex] units
By using the distance formula
Distance formula:[tex]\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
Side of big triangle =[tex]\sqrt{(1-1)^2+(-1+9)^2}=8[/tex] units
From given figure we can see that the pre-image is rotated about 180 degree and then we get big triangle.Therefore, the scale factor is negative.
Scale factor=[tex]-\frac{side\;of\;triangle}{side\;of\;small\;triangle}[/tex]
By using the formula
Scale factor=[tex]-\frac{8}{2}=-4[/tex]
Hence, the scale factor used to create the dilation=-4
