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Make sure that you list the PROPERTIES OF INEQUALITY (POI) in your G.B. ... they are as good as postulates or the properties of algebra when it comes for using them as REASONES in proofs.
As it states at the bottom of pg 203, anytime you use ANY POI in a proof, you simply write as your reason "A property of inequality"... you do not have to be specific.
In the case of #6 stmt 4, one of the POI's states that "If a=b+c and c>0, then a>b"... can you see how that works based on statement #3 (which was supported by the Seg Addition Post)?
In prob#7, the same POI (same logic) supports stmt #3. For stmt #4, recall stmt #1, so a simple "Substitution" is your reason.
I dont know where this goes, but here is the proof for #13 on p.207. 1) point k is in triangle abc (given) 2)m. angle C + m. angle A + m. angle B= 180 m. angle K + m. angle KBA + m. angle KAB = 180(the sum of the angles in a triangle is 180- thm 3-11) 3)measure of angle CBK + m. angle KBA = m. angle B M. angle CAK + m. angle KAB = m. angle A (angle addition post.) 4.)m. angle C + m. angle CAK + m. angle KAB + m. angle CBK + m. angle KBA = m. angle K + m. angle KBA + m. angle KAB (substitution property of equality) 5) m. angle K = m. angle C + M. angle CAK + m. angle CBK (subtraction property of equality) 6) m. angle K > m. angle C (a property of inequality (if a=b+c and c>0, then a>b)) -David
hey, didnt see the homework thats due so i'll post my q here.... its probably just me but i dont fully understand what angle of attack (haha, i said angle) that i should take on #'s 9 and 11 on pg 207
Well, in #9, you are comparing two "large" angles that each consist of two "smaller" angles... one of the angles they share in common, and you know something about the other two angles from the "given" info...
In #11, you have an oppt'y to work b'wards as we did the other day in class. You know angl-4 cong angl-3 (vert ang's)... do you know something about angl-3 vs. angl-2... then something about angl-2 vs. angl-1... ca-peesh?
idk what happned bu for some reason my entire proof got deleted except for the first and last sentences i had it al written out but something happned with my comptor sry
i don't know how to find the reasons for pg 206 #6 reson 4 and #7 resons 3 and 4
ReplyDelete-Natasha=)
Make sure that you list the PROPERTIES OF INEQUALITY (POI) in your G.B. ... they are as good as postulates or the properties of algebra when it comes for using them as REASONES in proofs.
ReplyDeleteAs it states at the bottom of pg 203, anytime you use ANY POI in a proof, you simply write as your reason "A property of inequality"... you do not have to be specific.
In the case of #6 stmt 4, one of the POI's states that "If a=b+c and c>0, then a>b"... can you see how that works based on statement #3 (which was supported by the Seg Addition Post)?
In prob#7, the same POI (same logic) supports stmt #3. For stmt #4, recall stmt #1, so a simple "Substitution" is your reason.
Ca-peesh?
Happy New Year!
Mr. C.
I dont know where this goes, but here is the proof for #13 on p.207.
ReplyDelete1) point k is in triangle abc (given)
2)m. angle C + m. angle A + m. angle B= 180
m. angle K + m. angle KBA + m. angle KAB = 180(the sum of the angles in a triangle is 180- thm 3-11)
3)measure of angle CBK + m. angle KBA = m. angle B
M. angle CAK + m. angle KAB = m. angle A (angle addition post.)
4.)m. angle C + m. angle CAK + m. angle KAB + m. angle CBK + m. angle KBA = m. angle K + m. angle KBA + m. angle KAB (substitution property of equality)
5) m. angle K = m. angle C + M. angle CAK + m. angle CBK (subtraction property of equality)
6) m. angle K > m. angle C (a property of inequality (if a=b+c and c>0, then a>b))
-David
Hi David, you posted in the right place... NICE JOB!
ReplyDeletehey, didnt see the homework thats due so i'll post my q here.... its probably just me but i dont fully understand what angle of attack (haha, i said angle) that i should take on #'s 9 and 11 on pg 207
ReplyDeleteWell, in #9, you are comparing two "large" angles that each consist of two "smaller" angles... one of the angles they share in common, and you know something about the other two angles from the "given" info...
ReplyDeleteIn #11, you have an oppt'y to work b'wards as we did the other day in class. You know angl-4 cong angl-3 (vert ang's)... do you know something about angl-3 vs. angl-2... then something about angl-2 vs. angl-1... ca-peesh?
lmk if this helped... Mr. C.
i dont understand how to make a conditional into a venn diagram
ReplyDeletei know that david already posted a proof but u said maby the second too so here goes.
ReplyDeletepoint k lies inside tri. ABC that is given. m M<K because of a POI
idk what happned bu for some reason my entire proof got deleted except for the first and last sentences i had it al written out but something happned with my comptor sry
ReplyDeleteWe'll check out some Venn Diagram examples in class today... lmk if it helps... Mr. C.
ReplyDeletehow can you prove #17 on 217 i read the answer on the back but it dosent make sence
ReplyDelete