Question

Solve the following pair of equations by using the substitution method x+2y=_1 2x_3y=12

Answer 1

Given:

• x+2y = -1
• 2x -3y = 12

We have to solve these equations using Substitution Method.

To find:

• The value of x and y

Solution:

We have,

x+2y = -1 -------(1)

2x -3y = 12 ----(2)

From eq(1), we will find the value of x

$\implies \text{x +2y = -1 }\\ </p><p> \implies \text{x = -1 -2y } - - (3)$

We will substitute the value of x in eq(2)

$\implies \text{2( - 1 - 2y) - 3y = 12} \\ \\ \implies \text{ - 2 - 4y - 3y = 12} \\ \\ \implies \text{ - 4y - 3y = 12 + 2} \\ \\ \implies \text{ - 7y = 14} \\ \\ \implies \text{y = } - \frac{14}{7} \\ \\ \implies \boxed{ \text{{ \green{y = - 2}}}}$

Now, we will substitute the value of y in eq(3)

$\implies \text{ x = - 1 - 2( - 2)} \\ \\ \implies \text{x = - 1 + 4} \\ \\ \implies \boxed {\text{ \green{x = 3}}}$

Hence, the value of x = 3 and y = -2