Question

∆ADC is formed by reflecting ∆ABC across line segment AC, as shown in the figure.

If the length of AC is 4 units, the area of ∆ADC is_
square units.

https://cdn.ple.platoweb.com/EdAssets/b11f175f3be6466e8db50c7889205198?ts=635376100595900000

Answer 1

If you reflect a figure, the preimage is congruent to the image.
If you reflect triangle ABC, it becomes triangle ADC.
So ABC is congruent to ADC.

Answer 2

If EB is 3, then ED is also 3.

Answer 3

I know they are congruent but I dont know how to solve it.

Answer 4

Do you know how to find the area of triangle ABC?
Area of a triangle is (1/2)*base*height.
base is AC = 4
height is EB = 3

Answer 5

2*3 so 6?

Answer 6

?

Answer 7

Yes, the area of ABC is 6. But you know that ABC is congruent to ADC, and if two figures are congruent their areas will be the same.

Answer 8

Thank you.

Answer 9

No problem.