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If DB = 24, AE = 3, and EC= 18, what is AD?

Answer 1

Savannah Aguilar

#AD=4#

According to the Triangle Proportionality Theorem parallel lines cut triangles into proportional parts.

We can see in the diagram that #DE# and #BC# are parallel.

So we can assume:

#(AD)/(DB)=(AE)/(EC)#

From there we can just solve:

#(AD)/(24)=(3)/(18)#

#AD=(3*24)/(18)#

#AD=(72)/(18)#

#AD=4#

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Answer 2

Carson Arnold

To find AD, we can use the property of similar triangles. Triangles ADE and ABC are similar since they share angle A and have parallel sides (DE and BC) due to transversals AE and DC.

Using the property of similar triangles:

AD/AB = AE/AC

Substituting the given values:

AD/ (AD + DB) = AE/(AE + EC)

Solving for AD:

AD/(AD + 24) = 3/(3 + 18)

AD/(AD + 24) = 3/21

Cross multiply:

21AD = 3(AD + 24)

21AD = 3AD + 72

18AD = 72

AD = 72/18

AD = 4

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.