Question

(2) x + 7y = 10; 3x - 2y = 7​

Answer 1

Answer:

x+7y=10; ------------(I)

3x−2y=7 -----------(II)

multiplying (I) with 3

3x+21y=30; ---------(III)

3x−2y=7 ---------------(IV)

Subtracting (IV) from (III) we get

3x+21y−3x+2y=30−7

23y=23

⇒1

Putting the value of y in (IV) we get

3x−2(1)=7

⇒3x=7+2=9

⇒3x=9

⇒x=3

Thus, (x,y)=(3,1)

Answer 2

x+7y=10. -(1)

3x-2y=7. -(2)

multiplying 3 in equation (1)

We get. 3x+21y=30

Now substrate equation 2 from equation 1

3x+21y=30

3x-2y. =7

_____________

23y=23

y=1

Now putting the value of y in equation 2 we get

3x-2*1=7

3x=9

x=3