Question

4. Which of the following is not<br />equivalent to -6/21<br />A. 20/-70<br />B. 10/-35<br />C.-9/24<br />D.-26/91​

Answer 1

Consider the equations:

3x−4y=25...(1)

−2x+y=−10...(2)

Multiply equation (2) by 4, we get

−2x(4)+y(4)=−10(4)

⇒ −8x+4y=−40...(3)

Now add equation (1) and (3), we get

3x−8x−4y+4y=25−40

⇒−5x=−15

⇒x=3

Substitute x=3 in equation (2)

−2(3)+y=−10

⇒−6+y=−10

⇒−y=−10+6

⇒−y=−4

Hence, x=3 and y=−4