5. The sides of an equilateral triangle are
(6x + 3y) cm, (8x + 9y – 5) cm and (10x + 12y -
8) respectively. Find the length of each side.
[Hint. Take 6x + 3y = 8x + 9y - 5 and
8x + 9y – 5 = 10x + 12y - 8 as two equations.]
Answers
Answer:
Step-by-step explanation:
Sides = 6x + 3y) cm, (8x + 9y – 5) cm and (10x + 12y - 8)
Since, sides of equilateral triangle are equal
Take 6x + 3y = 8x + 9y - 5
6x - 8x = 9y - 3y - 5
-2x = 6y - 5
2x + 6y = 5 -----------eq1
8x + 9y – 5 = 10x + 12y - 8
8x - 10x + 9y - 12y = 5 - 8
-2x - 3y = -3 ----------eq2
Multiply eq2 by -1
2x +3y = 3
By elimination method
2x + 6y = 5 -----------eq1
2x +3y = 3 ------------eq2
- - = - subtraction
_______________________
3y = 2
y = 2/3
Put the value of y in eq 1
2x + 3x 2/3 = 5
2x + 2 = 5
x = 1
(6x + 3y) cm, (8x + 9y – 5) cm and (10x + 12y -8)
= (6x1 + 3x2/3)cm , ( 8x1 + 9x2/3 - 5 )cm, ( 10x1 +12x2/3 -8) cm
= 8, 9 , 10 lenght