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4 votes
4x-3y=2
3x=5y=16
solve using substitution method

1 Answer

2 votes


\left\{\begin{array}{ccc}4x-3y=2&|\text{add 3y to both sides}\\3x+5y=16\end{array}\right\\\left\{\begin{array}{ccc}4x=3y+2&|\text{divide both sides by 4}\\3x+5y=16\end{array}\right\\\left\{\begin{array}{ccc}x=0.75y+0.5&(*)\\3x+5y=16\end{array}\right\\\\\text{substitute}\ (*)\ \text{to the second equation}\\\\3(0.75y+0.5)+5y=16\qquad\text{use distributive property}\\\\(3)(0.75x)+(3)(0.5)+5y=16\\\\2.25y+1.5+5y=16\qquad\text{subtract 1.5 from both sides}\\\\7.25y=14.5\qquad\text{divide both sides by 7.25}


\boxed{y=2}\\\\\text{substitute the value of y to}\ (*):\\\\x=0.75(2)+0.5\\\\x=1.5+0.5\\\\\boxed{x=2}\\\\Answer:\ x=2\ and\ y=2\to(2,\ 2)

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