Question

solve by elimination mathod 3x-5y=4 , 9x-2y​

Answer 1

Answer:

$\sf 3x-5y=4\dots\dots (1)$

$\sf 9x-2y=0 \dots\dots (2)$

• By multiplying eq (1) by 3 and eq (2) by 1 we get

$\qquad{:}\longrightarrow$$\sf 9x-15y=12\dots\dots (3)$

$\qquad{:}\longrightarrow$$\sf 9x-2y=0\dots\dots(4)$

• by subtracting eq (4) from eq (3) we get

$\qquad{:}\longrightarrow$$\sf -13y=-12$

$\qquad{:}\longrightarrow$$\sf 13y=12$

$\qquad{:}\longrightarrow$$\bf y=\dfrac {12}{13 }$

• Substitute the value of y in Equation 2

$\qquad{:}\longrightarrow$$\sf 9x-2 \left (\dfrac {12 }{13}\right)=0$

$\qquad{:}\longrightarrow$$\sf 9x-\dfrac {14}{13}=0$

$\qquad{:}\longrightarrow$$\sf 9x=\dfrac {14}{13}$

$\qquad{:}\longrightarrow$$\sf x={\dfrac {14}{13×9}}$

$\qquad{:}\longrightarrow$$\sf x=\dfrac {14}{117}$

$\therefore{\underline{\boxed{\bf (x,y)=(\dfrac {12}{13},\dfrac {14}{117})}}}$