Which pairs of triangles must be similar?

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20+ ! come and answer quick! triangle mno is reflected over the x-axis and then translated up 4 and right 3. how can the transformation be amended such that the translation can occur before the reflection and have the image remain in the same position? a translate the pre-image down 4 and right 3 and then reflect the figure over the x-axis. b translate the pre-image up 3 and right 4 and then reflect the figure over the x-axis. c translate the pre-image up 4 and left 3 and then reflect the figure over the y-axis. d translate the pre-image down 3 and right 4 and then reflect the figure over the x-axis.

Bob is putting books on a shelf and takes a break after filling 18 1/2 inches on the book shelf. the book shelf is now 2/3 full. how long is the entire bookshelf?

Gabriel determined that his total cost would be represented by 2.5x + 2y – 2. his sister states that the expression should be x + x + 0.5x + y + y – 2. who is correct? explain.