Question

How do you solve a system of equations by substitution and/or elimination?

Answer 1

x + y = 5
x - y = 2
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Substitution
solve the top one for x or y
eg
y = 5 - x
substitute that (5-x) for y in the second one
x - (5-x) = 2
2 x -5 = 2
2 x = 7
x = 3.5
then y = (5-x) = 1.5
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elimination
get magnitude of the coefficient of one of them the same in each equation then add or subtract
for example here I could add or subtract
x + y = 5
x - y = 2
-------------- add
2 x + 0 = 7
x = 3.5 again etc