Answer:
The length of DE is 14 cm.
Step-by-step explanation:
Given in triangle ABC segment DE is parallel to the side AC . (The endpoints of segment DE lie on the sides AB and BC respectively). we have to find the length of DE.
Given lengths are AC=20cm, AB=17cm, and BD=11.9cm
In ΔBDE and ΔBAC
∠BDE=∠BAC (∵Corresponding angles)
∠BED=∠BCA (∵Corresponding angles)
By AA similarity rule, ΔBDE~ΔBAC
∴their corresponding sides are in proportion
⇒ 
⇒ 
⇒ 
⇒ 
9514 1404 393
Answer:
7 in
Step-by-step explanation:
For width w in inches, the length is given as 2w+1. The area is the product of length and width, so we have ...
A = LW
105 = (2w +1)w
2w^2 +w -105 = 0
To factor this, we're looking for factors of -210 that have a difference of 1.
-210 = -1(210) = -2(105) = -3(70) = -5(42) = -6(35) = -7(30) = -10(21) = -14(15)
So, the factorization is ...
(2w +15)(w -7) = 0
Solutions are values of w that make the factors zero:
w = -15/2, +7 . . . . . negative dimensions are irrelevant
The width of the rectangle is 7 inches.