9514 1404 393
Answer:
x = 10
Step-by-step explanation:
The marked sides are proportional, so we have ...
x/8 = (x +5)/12
3x = 2(x +5) . . . . . multiply by 24 to clear fractions
3x = 2x + 10 . . . . . eliminate parentheses
x = 10 . . . . . . . . . . subtract 2x
_____
<em>Alternate solution</em>
We observe that the difference between the upper segment lengths is ...
(x +5) -(x) = 5
and the difference between the lower segment lengths is ...
12 -8 = 4
This means the upper segment lengths are 5/4 times as long as the lower segments. Then ...
x = (5/4)(8) = 10
Answer:
Remember that for a subset of a ring to be an ideal it must be closed under addition and under taking multiples by elements of the ring, and in this case the set of all composite integers is not closed under addition.
Step-by-step explanation:
2 1/2
4 can only go into 10 twice and you are left with 2/4 which can be simplified to 1/2