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11 votes
11 votes
Find x step by step ​

Find x step by step ​-example-1
User HMT
by
2.5k points

2 Answers

13 votes
13 votes

Answer:

x = 11 cm

Explanation:

Segments DE and BC are parallel (that's what the arrows tell you), so there are two similar triangles formed.


\triangle{ADE} \sim \triangle{ABC}

Corresponding sides are in proportion, so


(AD)/(AB)=(12)/(16)

The length of AB is (x + 1) + 4 = x + 5, and 12/16 simplifies to 3/4, so


(x+1)/(x+5)=(3)/(4)

"Cross multiply" to get


4(x+1)=3(x+5)\\4x+4=3x+15\\4x=3x+11\\x=11

User Oussama Jabri
by
2.5k points
30 votes
30 votes

Answer:


(4 + (x + 1))/(x + 1) = (16)/(12) \\ \\ (5 + x)/(x + 1) = (16)/(12) \\ \\ 12(5 + x) = 16(x + 1) \\ 60 + 12x = 16x + 16 \\ 4x = 44 \\ x = 11

User Aednichols
by
3.4k points