Question

What are x and y if x+y=4 and y=−7x+4?

Answer 1

Solution:

Given system of equations:

x+y = 4 ----(1)

y = -7x+4 ---(2)

Substitute (2) in equation (1),

we get

x -7x+4 = 4

=> -6x = 4-4

=> -6x = 0

=> x = 0

Put x = 0 in equation (2),we get

y = -7×0 + 4

=> y = 4

Therefore,

x=0,

y = 4

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