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3 years ago

Solve by substitution x-y=-11 y+7=-2x

Mathematics

1 answer:

Bess [88]3 years ago

4 0

x - y = - 11 .............( 1 )

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

from equation ( 1 )

x - y = - 11

x = -11 + y ...........( 3)

putting x in equation ( 2 )

y + 7 = - 2 x

y + 7 = -2 ( -11 + y ) y + 7 = 22 - 2 y y + 2 y =22 - 7

3 y = 15 y = 15 / 3

putting value of y in equation 3

x = -11+ ( 13 /5 ) x = -33 /3 + 15 / 3 ( l.c.m)

x = -17 / 5

check

x = -11 + y

- 17 / 5 = -11 + 13 / 5

-17 /5 = -17 / 5

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