<PRE><B>Question 403159</B>
equation using substitution method
y = 2/3x - 1
2x + 3y = 21


2x + 3(2/3x - 1) = 21 {substituted 2/3x - 1 in for y into bottom equation}
2x + 2x - 3 = 21 {used distributive property}
4x - 3 = 21 {combined like terms}
4x = 24 {added 3 to both sides}
x = 6 {divided both sides by 4}


y = 2/3x - 1
y = 2/3(6) - 1 {substituted 6 in for x into top original equation}
y = 4 - 1 {multiplied 2/3 by 6}
y = 3 {combined like terms}


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