Question

solve the pair of equation by method of elimination by equating coefficients : 1.) 3-(x-5)=y+4 and 2 (x+y)=4-3y

Answer 1

Given: the pair of equations

• 3 - (x - 5) = y + 4
• 2 (x + y) = 4 - 3y

To find: the required solution by method of elimination

Solution:

The given equations are

• 3 - (x - 5) = y + 4 or, x + y = 4 ... ...(1)
• 2 (x + y) = 4 - 3y or, 2x + 5y = 4 ... ...(2)

Multiplying (1) no. equation by 2 and (2) no. equation by 1, we get

• 2x + 2y = 8
• 2x + 5y = 4

On subtraction, we get

• 3y = 4 or, y = - 4/3

Putting y = - 4/3 in (1), we get

• x - 4/3 = 4
• or, x = 4 + 4/3
• or, x = 16/3

Answer: The required solution is

• x = 16/3, y = - 4/3.