Question

144. Solve this system of equation.3x - 5y = 4-2.c + 6y = 18

Answer 1

Let:

$\begin{gathered} 3x-5y=4_{\text{ }}(1) \\ -2x+6y=18_{\text{ }}(2) \end{gathered}$

From (1) solve for x:

$x=\frac{4+5y}{3}_{\text{ }}(3)$

Replace (3) into (2):

$\begin{gathered} -2(\frac{4+5y}{3}_{\text{ }})+6y=18 \\ -\frac{8}{3}-\frac{10}{3}y+6y=18 \\ -8-10y+18y=54 \\ 8y=54+8 \\ 8y=62 \\ y=\frac{62}{8} \\ y=\frac{31}{4} \\ y=7.75 \end{gathered}$

Replace the value of y into (3):

$\begin{gathered} x=\frac{4+5(\frac{31}{4})}{3} \\ x=\frac{57}{4} \\ x=14.25 \end{gathered}$