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Solve by substitution?
y=4x-9
y=x-3

1 Answer

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We have such system

\left \{ {{y=4x-9} \atop {y=x-3}} \right.
We can take first equation and put value of y in terms of x into second eq, so
y=x-3
4x-9=x-3 now we can solve it
4x-9=x-3 /-x both sides
3x-9=-3 /+9 both sides
3x=6 /:3 divide by 2 both sides
x=2 --- its the result
User Glenn Posadas
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