Answer:
23. x = 4; DE = 44
24. x = 25; DS = 28
Explanation:
23. Point S is the midpoint of DE, so ...
DS = SE
3x +10 = 6x -2
12 = 3x . . . . . . . . . add 2-3x
4 = x . . . . . . . . . . . divide by 3
Then DS has length ...
DS = 3x +10 = 12 +10 = 22
and DE is twice that length, so ...
DE = 44
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24. DS is half the length of DE, so is ...
DS = DE/2 = 56/2
DS = 28
Then x can be found from ...
DS = x +3
28 -3 = x = 25 . . . . . substitute value for DS
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Comment on problem 24
Sometimes it is easier to work parts of a problem out of sequence. Here, finding DS first makes finding x easier.