Question

using substitutionmethod 5x+2y=13 ,7x-5y=26

Answer 1

Heya !!!





5X + 2Y = 13 ------(1)



7X - 5Y = 26 --------(2)



From equation (1) we get,



5X + 2Y = 13



5X = 13-2Y


X = (13-2Y/5) -----(3)



Putting the value of X in equation (3) we get,



7X - 5Y = 26


7 × (13-2Y/5) - 5Y = 26



91 - 14Y/5 - 5Y = 26



91 - 14Y - 25Y/5 = 26




-39Y +91 = 5 × 26




-39Y +91 = 130




-39Y = 130-91


-39Y = 39



Y = 39/-39



Y = -1




Putting the value of X in equation (3)



X = 13-2Y/5 => 13 - 2 × -1/5




X = 13+2/5= 15/5




X = 3.


Hence,




X = 3 and Y = -1



HOPE IT WILL HELP YOU...... :-)

Answer 2

Heya !!!

Here is your answer.

Given :
5x + 2y = 13. .....(i)
7x -5y = 26. ....(ii)

Using (ii),
$7x - 5y = 26 \\ x = \frac{26 + 5y}{7}$

Now, Putting the value of x in eq. (i), we get....
$5( \frac{26 + 5y}{7} ) + 2y = 13 \\ = > \frac{130}{7} + \frac{25y}{7} + 2y = 13 \\ = > \frac{25y}{7} + \frac{14y}{7} = \frac{91}{7} - \frac{130}{7}$
=> 39y = -39
y = -1

Putting y = -1 in eq. (i), we get
5x -2 = 13
5x = 15
x = 3

Hence, x = 3 and y = -1.

Hope It Helps