Question

solve using elimination method
3x-y =8 and 7x+y=32​

Answer 1

Answer:

X= 4 and y = 4

hope this helps u..

Answer 2

Solution :

$\bf{\red{\underline{\bf{Given\::}}}}$

3x - y = 8 and 7x + y = 32

$\bf{\red{\underline{\bf{To\:find\::}}}}$

The value of x and y.

$\bf{\red{\underline{\bf{Explanation\::}}}}$

By using elimination method :

$\bullet\sf{3x-y=8....................(1)}\\\bullet\sf{7x+y=32..................(2)}$

A/q

We multiply equation (1) by 7 and equation (2) by 3, we get;

$\longrightarrow\sf{7(3x-y=8)}\\\\\longrightarrow\sf{21x-7y=56......................(3)}$

&

$\longrightarrow\sf{3(7x+y=32)}\\\\\longrightarrow\sf{21x+3y=96......................(4)}$

We subtracting equation (3) and (4),we get;

$\sf{21x-7y=56}\\\sf{21x+3y=96}\\\sf{(-) \:\:(-)\:\:\:(-)}\\------\\\:\:\:\sf{-10y=-40}$

$\longrightarrow\sf-{10y=-40}\\\\\longrightarrow\sf{y=\cancel{\dfrac{-40}{-10} }}\\\\\longrightarrow\sf{\pink{y=4}}$

Putting the value of y in equation (4),we get;

$\longrightarrow\sf{21x+3(4)=96}\\\\\longrightarrow\sf{21x+12=96}\\\\\longrightarrow\sf{21x=96-12}\\\\\longrightarrow\sf{21x=84}\\\\\longrightarrow\sf{x=\cancel{\dfrac{84}{21} }}\\\\\longrightarrow\sf{\pink{x=4}}$

Thus;

The value of x = 4 and y = 4 .