Question

3x+5y=7 and 11x-13y=9 solve by substitution method

Answer 1

get the value of x from first equation and then put it into second equation.you will get the value of y then put this value of y in previously found value of x ie(in eq.3).

Answer 2

Answer:

x = 68/47, y = 25/47

Step-by-step explanation:

We have been given the equation

3x +5y = 7........(1)

11x-13y =9 ........(2)

Solve for y in equation (1),

$5y=-3x+7\\y=-\frac{3}{5}x+\frac{7}{5}$

Plugging this value of y in equation 2

$11x-13(-\frac{3}{5}x+\frac{7}{5})=9\\\\11x+\frac{39}{5}x-\frac{91}{5}=9\\\\55x+39x=136\\\\94x=136\\\\x=\frac{68}{47}$

Thus, the value of y is

$y=-\frac{3}{5}\cdot\frac{68}{47}+\frac{7}{5}\\\\y=\frac{25}{47}$