In equilateral triangle ABC, AB=3x+3, and AC=5x-7, Line AM is a median. Find CM
2006-12-11 14:34:30 · 11 answers · asked by Kate! 3 in Entertainment & Music ➔ Polls & Surveys
CM=9
If AB =3x+3
and AC=5x-7
AB=AC right?
so, 3x+3=5x-7
Put all like terms together
3+7=5x-3x
10=2x
5=x
Substitute
AB=3x+3
=3(5)+3
=15+3
=18
AC= 5x-7
=5(5)-7
=25-7
=18
Now, AM is a median and so is CM
18 divided by 2 =9
CM=9
2006-12-11 14:42:21 · answer #1 · answered by BookLady 3 · 0⤊ 0⤋
In an equilateral triangle, all three sides are equivalent.
Set AB = AC and solve for x.
Substitute x back into the equation for AC = 5x - 7 to find the length of that side (which will be the length of all three sides). Since the median AM divides the side AC in half, take the length of the side and divide it by two.
2006-12-11 22:43:40 · answer #2 · answered by rockchalk 2 · 0⤊ 0⤋
Alright so the answer is 2.5.
I got this by setting 3x+3=5x-7. You know this by the definition of an equilateral triangles. All sides are the same. From solving that equation (subtracting 3x, and then adding 7 to both sides) you get that x=5.
Since CM is half of CB (which is 5) then CM is 2.5
Hope that helps!
2006-12-11 22:38:41 · answer #3 · answered by equinebeing 2 · 0⤊ 1⤋
since it is equilateral,
AB = AC
3x + 3 = 5x - 7
3x - 5x = - 7 - 3
- 2x = - 10
2x = 10
therefore, x = 5
therefore, the length of one side of the triangle is 18. ( by substituting x = 5 into one of the equations above. )
so since AB = AC = BC = 18,
CM = half of BC = 9.
therefore, CM = 9.
2006-12-11 22:39:46 · answer #4 · answered by Coin Soup 2 · 0⤊ 0⤋
3x+3=5x-7=2x+4=x=2
2006-12-11 22:42:06 · answer #5 · answered by jackiebrownjr 3 · 0⤊ 0⤋
I dont know i am not einstein lets see if you can figure it out
2006-12-11 22:37:13 · answer #6 · answered by yasi<3 2 · 0⤊ 0⤋
see ive never seen that before . im bearly in middle school
2006-12-11 22:37:26 · answer #7 · answered by Anita 5 · 0⤊ 0⤋
http://24season5.fanspeak.net/?C1951_528245
2006-12-11 22:36:07 · answer #8 · answered by Nora R 1 · 0⤊ 1⤋
9
edit _ Equine... x is not equal to one side!!
2006-12-11 22:36:17 · answer #9 · answered by ƎIΝΟƆ 6 · 1⤊ 0⤋
i'm not eistein
2006-12-11 22:36:32 · answer #10 · answered by ? 7 · 0⤊ 1⤋