Question

solve the following equations by using substitution method 3x+4y=4, 5x-3y=26..also find the value of (2x+y)​

Answer 1

Answer:

x=4

y= -2

2x+y = 6

Step-by-step explanation:

3x + 4y = 4

4y = 4 - 3x

y = 4 - 3x/ 4

substitute value of y in 5x - 3y = 26

5x - 3( 4 - 3x/4) = 26

5x - (12-9x)/4 = 26

(20x - 12 -9x)/4 =26

20x- 12-9x= 26*4

29x-12= 104

29x= 104+12

29x = 116

x= 116/29

x=4

substitute value of x in y =4-3x/4

y= 4-3(4)/4

y= -2

2x +y = 2(4) + (-2)

2x+y= 6

Answer 2

Answer:

x=4 y= -2

2x+y = 6

Step-by-step explanation:

3x+4y=4

:. 4y=4-3x

:. y= 4-3x ----(1)

4

5x-3y=26 ------(2)

Substituting value of y in equation (2)

:. 5x- 3( 4-3x ) = 26

4

5x - 12+9x = 26

4

20x - 12 + 9x = 26

4

29x -12 = 104

:. 29x = 104 +12

:. 29x = 116

:. x = 116

29

:. x = 4

from (1)

y = 4 - 3(4)

4

y = 4-12

4

:. y = -8

4

:. y = -2

:. (2x+y) = 2(4) + (-2)

= 8 - 2

= 6

:. (2x+y) = 6