Question

Segment DE is midsegment of triangle ABC. What is the length of segment DE?

A) 5
B) 10
C) 15
D) 20

Answer 1

(X+5)2=X+15
2X+10=X+15
X=5
A) 5 :)

Answer 2

B) 10

Explanation:

If DE is midsegment of the triangle, we know that AC measures twice as DE.

In the problem we have that AC = x + 15 and DE = x + 5

Writing this as an equation we have:

`x + 15 = 2(x+5)\\x+15=2x +10\\15-10=2x-x\\5=x`

Therefore x = 5 and the length of segment DE is:

x + 5 = 5 + 5 = 10

Therefore the correct answer is B) 10