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2x-y=4 and y=-2x+8.

Can anyone help me solve

User Arpita
by
5.4k points

2 Answers

3 votes

Answer:

The value of x is 3 and y is 2

Explanation:

Here, 2x - y = 4 and y = -2x + 8 are two given equation,

Now, We will use Substitution Method

2x - y = 4 ...(1)

y = -2x + 8 ...(2)

Substitute the value of y = -2x + 8 in equation (1)

2x - y = 4

2x - (-2x + 8) = 4

2x + 2x - 8 = 4

4x - 8 = 4

Add 8 both side we get,

4x - 8 + 8 = 4 + 8

4x = 12

Divide by 4 both side we get,

4x/4 = 12/4

x = 3

Now, Substitute the value of x in equation (2)

y = -2x + 8

y = -2(3) + 8

y -6 + 8

y = 2

Thus, The value of x is 3 and y is 2

FOR VERIFICATION ONLY:

2x - y = 4

2(3) - (2) = 4

6 - 2 = 4

4 = 4

y = -2x + 8

2 = -2(3) + 8

2 = -6 + 8

2 = 2

Hence, L.H.S = R.H.S

-TheUnknownScientist

User Antonakos
by
6.3k points
3 votes

Answer:

The correct answer is x = 3 and y = 2.

Explanation:

There are many ways to solve systems of equations like this, but I'm going to use substitution. This means taking the value of y given by the second equation and plugging it into the first equation. This is modeled below:

2x - y = 4

2x - (-2x+8) = 4

Now, we can simplify the left side of the equation.

2x + 2x - 8 = 4

4x - 8 = 4

We should add 8 to both sides as the next step.

4x = 12

Now we can divide by 4.

x = 3

To solve for y, we can substitute this value found for x back into either one of our original equations.

y = -2x + 8

y = (-2*3) + 8

y = -6 + 8

y = 2

Therefore, the correct answer is x = 3 and y = 2.

Hope this helps!

User Balraj
by
5.8k points