Question

subtituatin method of class9 solve this question x+4y=13 and 7x-3y=29 ​

Answer 1

Solve $x+4y=13$ and $7x-3y=29$ by substitution method

Definition:

The substitution method is the algebraic method to solve simultaneous linear equations.As the word says,in this method,the value of one variable from one equation is substituted in the other equation.

Step-by-step explanation:

$x+4y=13$      (1)

$7x-3y=29$    (2)

Multiply equation (1) by 7,so

$7x+28y=91$     (3)

Subtract (2) and (3)

$7x+28y=91$

$7x-3y=29$

(-)   (+)     (-)

__________

[tex]31y=62\\ y=\frac{62}{31} \\ y=2[/tex]

Substitute $y=2$ in equation (1)

[tex]x+4y=13\\ x+4(2)=13\\ x+8=13\\ x=13-8\\ x=5[/tex]

Therefore,by substitution method the value of x is 5 and y is 2.