<h3>
Answer: choice B) 2 by 6</h3>
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How I got that answer:
Opposite sides of the rectangle are the same length, so
y = 2x-4 (horizontal sides)
3y = x+3 (vertical sides)
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Start with the second equation. Replace the 'y' with (2x-4) which is from the first equation. This replacement will allow us to solve for y
3y = x+3
3(2x-4) = x+3 .. replaced y with (2x-4)
6x-12 = x+3 ... distribute
6x-12+12 = x+3+12 ..... add 12 to both sides
6x = x+15
6x-x = x+15-x ..... subtract x from both sides
5x = 15
5x/5 = 15/5 ........ divide both sides by 5
x = 3
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Now we know the value of x, which means we can find the value of y
y = 2x-4
y = 2*3-4 .... replace x with 3
y = 6-4
y = 2
So the horizontal side is 2 units long
The vertical side is therefore 3y = 3*2 = 6
or we can say x+3 = 3+3 = 6 getting the same answer
