We know that the area is 20.
Since 20 is a small number: lets list out possible combinations of lengths and widths.
1 * 20
2 * 10
4 * 5
L = 7 + 3w
lets see which on makes sense.
L = 7 + 3w
20 = w7 + 3w^2
3w^2 + 7w -20 = 0
(3w - 10)(w - 2)
w can equal 10/3 or 2.
So the dimensions: are Width = 2 Length = 10
2x+2y =50
2(7)+ 2(3)=50
14+6 =50
20=/=50
This is false because when you substitute the variables with their numbers and then multiply and add, your answer does not equal 50
Basically you need to make the denominator (whats on the bottom) the same, lets take the first one for example
2 3/4, lets put this all over 4 for the same denominator.
2=8/4, and then add this to 3/4 to get 11/4.
the second part will work the same way,
start by making 1 into 8/8. add this to 1/8 to get 9/8
now we have to add 11/4 and 9/8. to do this, you have to find the smallest multiple between the two (for example: between 6 and 4 it would be 12, since 4*3= 12, and 2*6=12)
now, the smallest common multiple between 4 and 8 would just be 8
11/4= 22/8, since you multiply the bottom and top by the same amount so it still equals 11/4, but your denominator will now be 8.
now you can subtract. 22/8- 9/8= 13/8
final answer: 13/8
try the rest yourself since this is important for later math, hoped this helped :)
3,4,5 are Pythagorean triplets. then 6,8,10 are, so the answer is 10
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