Question

Solve : x = -3y - 8; x - 2y = -3 *

a) x = 5, y = -1
b) x = -5, y = 1
c) x = -5, y = -1
d) x = 1, y = -5​

Answer 1

Given :

• x = -3 - 8
• x - 2y = -3

To find :

x & y

Procedure :

• Make a equation so to relate x & y
• Then substitute value of either x or y , from one equation into another
• And solve for one variable
• Thereafter, solve for other variable

Solution:

➝ x = -3y - 8 ..... equation 1

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➝ x - 2y = -3

On putting value of x from equation 1 into equation 2, we get;

➝ (-3y - 8) - 2y = -3

➝ - 3y -2y = -3+8

➝ -5y = 5

➝ y = 5 ÷ (-5)

➝ y = -1

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Putting value of y in equation 1, we get,

➝ x = -3(-1) - 8

➝ x = 3-8

➝ x = -5

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ANSWER :

option c) x = -5 & y = -1