Substitution Method

How do you solve this system of equations using the substitution method?
3x - 4y = 10
y = x - 3

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3x - 4(x - 3) = 10   {substituted x - 3, in for y, into top equation}
3x - 4x + 12 = 10   {used distributive property}
-x + 12 = 10   {combined like terms}
-x = -2   {subtracted 12 from both sides}
x = 2   {divided both sides by -1}

y = x - 3   {bottom equation}
y = 2 - 3   {substituted 2, in for x, into bottom equation}
y = -1   {subtracted}

x = 2 and y = -1

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