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Solve using substitution, 5x+y=9 10x-7y=-18

User Duval
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1 Answer

4 votes

Answer:

See below

Explanation:

5x + y = 9 re-arrange to y = 9-5x

use this value of 'y' in the second equation:

10x - 7(9-5x) = - 18

solve for x = 1

sub in this value of 'x' into one of the equations to compute 'y'

5 (1) + y = 9

y = 4

User Jamie Chong
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