Giving 50 and brainiest stretch △def with points d(−2, 1), e(−1, −1), and f(−2, −2) horizontally and vertically by a factor of 4. stretching △def horizontally and vertically by a factor of 4 results in the transformed points d' e' f'

For this case we have to apply the following transformation:
 (x, y) > (4x, 4y) > (x ', y')
 Applying the transformation to the vertices we have:
 (-2, 1) > (4 (-2), 4 (1)) > (-8, 4)
 (-1, -1) > (4 (-1), 4 (-1)) > (-4, -4)
 (-2, -2) > (4 (-2), 4 (-2)) > (-8, -8)
 
 Stretching △DEF horizontally and vertically by a factor of 4 results in the transformed points 
 D '(-8, 4)
 E '(-4, -4)
 F '(-8, -8)

Number nine is f(x)= 40x : ) hoped i ya