To find the answer to #1 we need to use substitution to replace the variables with numbers
(-3,-2)
Substitute
(7)(-3) - (5)(-2) = 28
(7)(-3) - (5)(-2) Does not equal 28
(4,0)
Substitute
(7)(4) - (5)(0) = 28
This is true
(4,0) is your answer
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2.)
4x - 5y = 9
y = 4/5x - 9/5
