Question

5x+2y=-3;x+5y=4 substituting method​

Answer 1

Solution:

Given system of equations:

5x+2y= -3 ----(1)

x +5y = 4

=> x = -5y+4 ----(2)

Substitute (2) in equation (1),

we get

=> 5(-5y+4)+2y=-3

=> -25y+20+2y = -3

=> -23y = -3 -20

=> -23y = -23

=> y = (-23)/(-23)

=> y = 1

Now ,

put y = 1 in equation (2), we get

x = -5×1 +4

=> x = -5 + 4

=> x = -1

Therefore,

x = -1 , y = 1

•••

Answer 2

Answer:

5x + 2y = –3 .....(I)

x + 5y = 4 .....(II)

Multiply (II) with 5 we get

5x + 25y = 20 .....(III)

Subtracting (III) from (I) we get

5x−5x+2y−25y=−3−20

⇒−23y=−23

⇒y=−23−23=1

Putting the value of y = 1 in (II) we get

x+5(1)=4⇒x+5=4⇒x=4−5=−1

Thus, (x, y) = (−1, 1)