Question

Draw the graph of linear equation 3x-7y=21. Check whether (8,1) is a solution of

the given equation or not.​

Answer 1

3x=7y−21

(i)3x=7y−21

If x=0 we get

3×0=7y−21

⇒7y−21=0

⇒7y=21

⇒y=3

(0,3)

(ii)3x=7y−21

If y=0 we get

3x=7×0−21

⇒3x=21

⇒3x=21

⇒x=3

(3,0)

(iii)3x=7y−21

If x=1 we get

3×1=7y−21

⇒3=7y−21

⇒7y=21+3

⇒7y=24

⇒y=

7

24

(1,

7

24

)