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math

Solve:

3x−y=4
xy=5
McGenius McGenius
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Re: math

3x - y = 4
xy = 5

3x - y = 4   first equation
-y = -3x + 4   subtracted 3x
y = 3x - 4   divided by -1

xy = 5   second equation
x(3x - 4) = 5   substituted 3x - 4 for y into second equation
3x² - 4x = 5   distributive property
3x² - 4x - 5 = 0   subtracted 5
 
Use graphing calculator or quadratic formula.

x ≈ 2.12 or -0.786
y ≈ 2.359 or -6.359



*McGenius*