Question

If 4x+3y=10, 3x+4y=-3 Then find the value of x+y​

Answer 1

Given :

• 4x + 3y = 10
• 3x + 4y = -3

To find :

x + y

Solution :

We are given two linear equations in two variables ( x & y) now we need to find the value of x and y individually and than add them to find (x+y)

• 4x + 3y = 10 equation 1
• 3x + 4y = -3 equation 2

Add equation 1 and 2, ( LHS of equation 1 will be added to LHS of equation 2 , and similarly RHS of equation 1 will be added to RHS of equation 2)

➝ ( 4x + 3y ) + ( 3x + 4y ) = 10 + ( -3 )

➩ ( 4x + 3x ) + ( 4y + 3y ) = 10 - 3

➩ 7x + 7y = 7

➩ 7(x+y) = 7

➩ (x+y) = 7/7

➩ (x+y) = 1

Note - Here we get the required value ( of x+y ) directly, so we don't need to find value of x and y seperately

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ANSWER : 1