Question

25 POINTS PLEASE HELP How do I solve {y=2x-4; x+2y=12}

Answer 1

Substitute y = 2x - 4 to x + 2y = 12:

x + 2(2x - 4) = 12    use distributive property

x + (2)(2x) + (2)(-4) = 12

x + 4x - 8 = 12     add 8 to both sides

5x = 20    divide both sides by 5

x = 4

Put the value of x to the first equation:

y = 2(4) - 4

y = 8 - 4

y = 4

Answer: x = 4 and y = 4

Answer 2

Answer:

x=4, y=4

Step-by-step explanation:

y=2x-4;

x+2y=12

We can use substitution since the first equation is solved for y

Where ever you see y in the second equation, replace it with 2x-4

x + 2(2x-4) = 12

Distribute the 2

x+4x-8 = 12

Combine like terms

5x-8=12

Add 8 to each side

5x-8+8=12+8

5x=20

Divide by 5

5x/5 = 20/5

x =4

We still need to solve for y

y = 2x-4

We know x =4

y = 2(4) -4

y = 8-4

y=4