Could someone please check my solution?

homeschool girl

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The Question

In the figure below, [MATH]D[/MATH] is a point on segment [MATH]\overline{CE}[/MATH] such that [MATH]\overline{AD}\parallel\overline{BE}[/MATH] and [MATH]A[/MATH] is not on [MATH]\overline{BC}[/MATH] Line segments [MATH]\overline{AD}[/MATH] and [MATH]\overline{BC}[/MATH] intersect at [MATH]P[/MATH].

5ca5a369cc108d2079bce7ee6ef51af69b30df3a.png


Can [MATH]\angle CAD=\angle CBE?[/MATH] Explain.


My Answer:

When you have a line that intersects two parallel lines, the 8 angles formed can be split into two groups of four congruent angles, we will extend the lines CB and ED to illustrate this better
1bc04c3f164656f77a9108bde34e4638f35f8e3d.png
98a87f39b4b7818fffbaeb3daed28c4647f422ec.png


[MATH]\overline{CE}[/MATH] is also a transversal of [MATH]\overline{AD}[/MATH] and [MATH]\overline{BE}[/MATH], so [MATH]\overline{PDC}=\overline{BEC}[/MATH].

e1f5761e6728a8994dc099b0c7a0a55b465bdf11.png


[MATH]\triangle PCD[/MATH] Shares [MATH]\angle BCE[/MATH] with [MATH]\triangle BCE[/MATH], so all angles on [MATH]\triangle PCD[/MATH] are equal to the angles on [MATH]\triangle BCE[/MATH]
Because [MATH]\triangle PCD[/MATH] is a triangle, [MATH]\angle{PCD}+\angle{PDC}+\angle{CPD}=180[/MATH], and because [MATH]A[/MATH] does not lie on [MATH]\overline{BC}[/MATH], [MATH]\angle{ACD}\neq\angle{PCD}[/MATH]. Assuming that [MATH]\angle CAD=\angle CPD=\angle CBE[/MATH] we get [MATH]\angle{ACD}+\angle{PDC}+\angle{CPD}=180[/MATH], but we just saw that [MATH]\angle{ACD}\neq\angle{PCD}[/MATH], which means that [MATH]\angle{CAD}+\angle{PDC}+\angle{CPD}[/MATH] cannot equal [MATH]180[/MATH], but thats impossable, which must mean that our assumption was wrong and that [MATH]\boxed{\angle CAD\neq\angle CBE}[/MATH]
 
The Question

In the figure below, [MATH]D[/MATH] is a point on segment [MATH]\overline{CE}[/MATH] such that [MATH]\overline{AD}\parallel\overline{BE}[/MATH] and [MATH]A[/MATH] is not on [MATH]\overline{BC}[/MATH] Line segments [MATH]\overline{AD}[/MATH] and [MATH]\overline{BC}[/MATH] intersect at [MATH]P[/MATH].

5ca5a369cc108d2079bce7ee6ef51af69b30df3a.png


Can [MATH]\angle CAD=\angle CBE?[/MATH] Explain.


My Answer:

When you have a line that intersects two parallel lines, the 8 angles formed can be split into two groups of four congruent angles, we will extend the lines CB and ED to illustrate this better
1bc04c3f164656f77a9108bde34e4638f35f8e3d.png
98a87f39b4b7818fffbaeb3daed28c4647f422ec.png


[MATH]\overline{CE}[/MATH] is also a transversal of [MATH]\overline{AD}[/MATH] and [MATH]\overline{BE}[/MATH], so [MATH]\overline{PDC}=\overline{BEC}[/MATH].

e1f5761e6728a8994dc099b0c7a0a55b465bdf11.png


[MATH]\triangle PCD[/MATH] Shares [MATH]\angle BCE[/MATH] with [MATH]\triangle BCE[/MATH], so all angles on [MATH]\triangle PCD[/MATH] are equal to the angles on [MATH]\triangle BCE[/MATH]
Using \(\Delta CAP\) and by the external angle sum theorem we know \(m(\angle CPD)>m(\angle CAP)\).
But \(m(\angle CPD)=m(\angle CBE)\) WHY? Thus \(\(m(\angle CAD)<(m(\angle CBE). DONE WHY?
 
m(∠CPD)=m(∠CBE) because AD and BE are parallel, right? the the original question asks whether or not mCAD=mCBE. I think that's what you're asking?
 
If the measure of one angle is greater that another angle then they have the same measure.
 
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