Maths-

General

Easy

Question

# Solve the system of equations by elimination :

3X + 2Y = 8

X + 4Y = - 4

Hint:

**HINT:** Perform any arithmetic operation and then find.

## The correct answer is: we get x = 4 and y = - 2

### Complete step by step solution:

Let 3x + 2y = 8…(i)

and x + 4y = - 4….(ii)

On multiplying (ii) with 3, we get 3(x + 4y=-4)

⇒3x + 12y = - 12…(iii)

Now, we have the coefficients of in (i) and (iii) to be the same.

On subtracting (i) from (iii),

we get LHS to be 3x + 12y - (3x + 2y) = 12y - 2y = 10y

and RHS to be - 12 - 8 = - 20

On equating LHS and RHS, we have 10y = - 20

⇒y = - 2

On substituting the value of y in (i), we get 3x + 2× - 2 = 8

⇒ 3x - 4 = 8

⇒ 3x = 8 + 4

⇒ 3x = 12

⇒x = 4

Hence we get x = 4 and y = - 2

Note: We can also solve these system of equations by making the coefficients of y

to be the same in both the equations

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