Question

How do you solve the system 4x−3y=34, 3x+9y=−42?

Answer 1

solution:-

4x-3y=34........(1)

3x+9y=-42.........(2)

multiply (1)eq by 3

12x-9y=102.........(3)

Add eq (2)and (3)

3x+9y=-42

12x-9y=102

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15x =60

x=60/15

x=4

substitute x=4 in eq (1)

4x-3y=34

4(4)-3y=34

16-3y=34

-3y=34-16

-3y=18

y=18/-13

y=-6

(x,y)=(4,-6) is the solution of above question