Geometry help?

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3 Answers
Mar 30, 2018

x=16 2/3

Explanation:

triangleMOP is similar to triangleMLN because all the angles of both triangles are equal.
This means that the ratio of two sides in one triangle will be same as that of another triangle so "MO"/"MP"="ML"/"MN"
After putting in values, we get x/15=(x+20)/(15+18

x/15=(x+20)/33

33x=15x+300

18x=300

x=16 2/3

Mar 30, 2018

C

Explanation:

We can use the Side-Splitter Theorem to solve this problem. It states:

  • If a line is parallel to a side of a triangle and intersect the other two sides, then this line divides those two sides proportionally.

Since OP || LN, this theorem applies.

So we can set up this proportion:
x/20 = 15/18

Now cross multiply and solve:
x/20 = 15/18

x xx 18 = 20 xx 15

18x = 300

x = 300/18 rarr 16 12/18 rarr 16 2/3

So the answer is C

Mar 30, 2018

Answer: x=16*2/3

Explanation:

Since OP is parallel to LN, we know that angleMOP=angleMLN and angleMPO=angleMNL from the Corresponding Angles Theorem

Further, we also have that angleOMP=angleLMN since they are the same angle.

Therefore triangleOMP is similar to triangleLMN (triangleOMP~triangleLMN)

Since similar triangles have the same side length ratio:
(MO)/(ML)=(MP)/(MN)

Plugging numbers in, we have:
x/(x+20)=15/(15+18)

We can now solve this equation by cross multiplication:
33x=15(x+20)
33x=15x+300
18x=300
x=16*2/3