Answer:
Its 13
Step-by-step explanation:
The triangle is drawn and is shown in the image attached with.
We get two similar triangles. Triangle ABC and Triangle ADE. Since the triangles are similar the ratio of their corresponding sides will be the same.
D and E are the midpoints of AB and BC, therefore, AD and AE are both 4 units in length. Using the property of similar triangles, we can say:
AD : DE= AB : BC
AD = 4 units
AB = 8 units
BC = 6 units
DE = unknown = x units
So,

Therefore,
the length of DE will be 3 units
Answer:
300
Step-by-step explanation:
X+10+10=8+10 is not equal to x=18. It must be x+20=18 x=-2
Answer:
D Not similar
Step-by-step explanation:
For similar triangles the sides are always in proportions.
Here two sides are in proportion but third side isn't. So triangles are not similar.