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3 years ago

Solve the simultaneous equations.

Mathematics

1 answer:

user100 [1]3 years ago

6 0

Answer:

x=3/2, y=-1/2

Step-by-step explanation:

2x+4y =1

3x-5y =7

We will use elimination to solve these

Multiply the first equation by 3

3(2x+4y =1) 6x +12y =3

Multiply the second equation by -2 so that the x coefficients are the opposites of each other (6 and -6)

-2(3x-5y =7) -6x +10y =-14

Add the two new equations together

6x +12y =3

-6x +10y =-14

--------------------

0 + 22y = -11

Divide each side by 22

22y/22 = -11/22

y = -1/2

Now we can substitute y=-1/2 into the first equation and solve for x

2x + 4y =1

2x +4(-1/2) =1

2x -2 =1

Add 2 to each side

2x-2+2=1+2

2x=3

Divide by 2

2x/2 =3/2

x = 3/2

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Step-by-step explanation:

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