Question

3 X + 4 Y = 10 2x- 2 Y=
2 substitution method

Answer 1

GIVEN

3x + 4y = 10 ...eq.01

2x - 2y = 2

=> 2(x - y) = 2

=> x - y = 1 ...eq.02

Now we can solve both the linear equations in two variable by substitution method :-

x = (10 - 4y)/3 (From eq. 01)

Substiuting the value of x in eq.02,

(10 - 4y)/3 - y = 1

=> (10 - 4y - 3y)/3 = 1

=> 10 - 7y = 3

=> - 7y = - 7

=> y = -7/-7

=> y = 1

Putting the values in eq. 01 ;

3x + 4y = 10

=> 3x + 4 = 10

=> 3x = 6

=> x = 2

Hence, x = 2 and y = 1

VERIFICATION

Putting both the values in Eq.02,

LHS = x - y

= 2 - 1

= 1

= RHS

Hence, LHS = RHS Our answer is correct

Answer 2

Answer:  x = 2 ; y = 1

Step-by-step explanation:

Given,

3x + 4y = 10    ...........i)

2x - 2y = 2      ..............ii)

Multiplying Eq. ii) by 2

4x - 4y = 4     ...........iii)

Now,

Adding eq i) and iii)

3x + 4y + 4x - 4y = 10 + 4

7x = 14

x = 14/7

x = 2  

Now, Putting x = 2 in equation ii)

2×2 - 2y = 2

4 - 2y = 2

4 - 2  = 2y

2 = 2y

2y = 2

y = 2/2

y = 1

Hence, x = 2 ; y = 1

Note:- This method is known as elimination method while second method is known as Substitution Method.