Question

Solve 3/7x +4/7 y=10 and x/7 – y/7=1 by elimination method.​

Answer 1

Answer:

x= - 52

y=49

Step-by-step explanation:

3/7x+4/7y=10

3x+4y=70

x/7-y/7=1

x-y =7

Multiply this by 3 on both sides

Then equation becomes :-

3x-3y=21

Use elimation method now

3x+4y=70

3x-3y=21

-___+_-____

y= 49 (put it into bove 1 equation)

3x+4(49)=70

3x=70-196

x= -156/3

x= - 52

Answer 2

Answer:

First we have to add 3x2 − 5x + 2 and − 5x2 − 8x + 9 then from the result we have to subtract 4x2 − 7x + 9. = {(3x2 – 5x + 2) + (- 5x2 – 8x + 9)} – (4x2 – 7x + 9) = {3x2 – 5x + 2 – 5x2 – 8x + 9} – (4x2 – 7x + 9) = {3x2 – 5x2 – 5x – 8x + 2 + 9} – (4x2 – 7x + 9 = {- 2x2 – 13x +11} – (4x2 – 7x + 9) = – 2x2 – 13x + 11 – 4x2 + 7x – 9 = – 2x2 – 4x2 – 13x + 7x + 11 – 9 = – 6x2 – 6x +