solve the following by the elimation and sublimation process 2x +3y = ; 3x +4y = 5
Answers
2x + 3y = 9 (i)
3x + 4y = 5 (ii)
multiple equation (i) by 3 and equation (ii) by 2
3(2x + 3y) = 3(9)
6x + 9y = 27 (iii)
2(3x + 4y) = 2(5)
6x + 8y = 10 (iv)
(iii) - (iv)
6x + 9y = 27
6x + 8y = 10
- - = -
y = 17
substitute the value of y in equation (i)
2x + 3*17 =9
2x + 51 = 9
2x = 9 - 51
2x = -42
x = -42/2
x = -21
therefore x = -21 and y = 17
by elimination method
2x + 3y = 9 equation 1st multiply by 4
3x + 4y = 5 equqtion 2nd multiply by 3
8x + 12y =36 equation 3rd
9x + 12y = 15 equation 4th ( by SUB.equ. 4 from 3)
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-x = 21
x = -21
put the value of x in equ. 1
2x + 3y = 9
2×-21 + 3y = 9
3y = 9 +42
y = 51/3
y = 17
by subsitutional method
2x + 3y =9 equation 1st
3x + 4y = 5 equation 2nd
from equ. 1st
x = 9 - 3y / 2
put the value of x in equ. 2nd
3x + 4y = 5
3(9-3y/2) + 4y = 5
27/2 -9y/2 +8y/2 = 5
27-y = 10
-y = 10 - 27
-y = -17
y =17
put the value of y in equ. 3rd
x = 9- 3y /2
x = 9-3×17/2
x= 9-51/2
x= 42/2
x= 21
hope it will be helpful for you