Question

solve 2x – y = 5 and 3x + 2y = 11 by substitution.

Answer 1

Answer:

The value of x=3 and y=1 is the solution.

Step-by-step explanation:

Given : Equations $2x- y=5 \text{ and } 3x+2y=11$

To solve : The given equations by substitution?

Solution :

Let  $2x- y=5$ ......[1]

$3x+2y=11$ .......[2]

Now, solving [1] and [2] by substitution method,

Substitute the value of x from [1] in [2]

$x=\frac{5+y}{2}$

$3x+2y=11$

$3(\frac{5+y}{2})+2y=11$

$\frac{15+3y}{2}+2y=11$

$\frac{15+3y+4y}{2}=11$

$15+7y=22$

$7y=22-15$

$7y=7$

$y=1$

Substitute the value of y=1 in [1]

$2x- y=5$

$2x- 1=5$

$2x=6$

$x=3$

Therefore, The value of x=3 and y=1

Answer 2

Answer:

2x − y = 5 .....(I)

3x + 2y = 11 .....(II)

Multiplying (I) with 2 we get

4x−2y=10 .....(III)

Adding (II) with (III)

7x=21⇒x=3

Putting the value of x in (I) we get

2×3−y=5

⇒6−y=5

⇒y=1