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Math Help?
6: Perimeter = 55. AB = 3x - 7. BC = 5x - 21. AC = 2x + 3
Equilateral
Isosceles
Scalene
7: Perimeter = 51. AB = 9 + x. BC = x. AC = x.
Equilateral
Isosceles
Scalene
1 Answer
- James LLv 51 decade agoFavorite Answer
6. Since the perimeter is 55, you get
3x-7 + 5x - 21 + 2x + 3 = 55
Combine like terms:
10x - 25 = 55
Solve for x:
10x = 80, so x = 80/10 = 8.
The sides are therefore
AB=3(8)-7 = 24-7=17
BC=5(8)-21 = 40-21=19
AC=2(8)+3 = 16+3=19
so it's isoceles.
7. Same approach:
9+x + x + x = 51,
so 9 + 3x = 51
=> 3x = 51-9 = 42
=> x = 42/3 = 14.
Therefore AB=9+14=23, BC=14 and AC=14. It's isoceles.
