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3 years ago

Y=2x+9 y=4x-9 Solve the system of equations.

Mathematics

2 answers:

sergij07 [2.7K]3 years ago

7 0

Answer:

x=9,y=27

Step-by-step explanation:

y=2x+9,........equation 1

y=4x-9..........equation 2

from equation 1 and 2

we get

2x+9=4x-9

9+9=4x-2x

x=18/2=9

substituting value of x in equation 1

y=2×9+9=18+9=27

Deffense [45]3 years ago

3 0

Answer:

Your solution is (9, 27) or x = 9, y = 27

Step-by-step explanation:

y = 2x + 9

y = 4x - 9

We can see that both of these equations equal y, so we can set them equal to each other.

2x + 9 = 4x - 9

Add 9 to both sides.

2x + 18 = 4x

Subtract 2x from both sides.

18 = 2x

Divide both sides by 2.

9 = x

Now we want to find y. To do this, plug x = 9 back into one of the original equations.

y = 2(9) + 9

Multiply.

y = 18 + 9

Add.

y = 27

Your solution is (9, 27)

Check your answer by plugging x = 9 and y = 27 back into the original equations.

y = 2x + 9

27 = 2(9) + 9

27 = 18 + 9

27 = 27

y = 4x - 9

27 = 4(9) - 9

27 = 36 - 9

27 = 27

Your answer is correct.

Hope this helps!

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