Answer:
23. x = 4; DE = 44
24. x = 25; DS = 28
Step-by-step 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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<em>Comment on problem 24</em>
Sometimes it is easier to work parts of a problem out of sequence. Here, finding DS first makes finding x easier.
Answer: He actually rode 2 miles per hour on his trip
Step-by-step explanation: Maybe unconventional, but express the time it took, then figure the speed.
Time = distance /speed t will represent time, s is the speed: t = 30/s Use the rime it would have taken at the higher speed to create an equation:
t-12 = 30/s+8 replace the y with the 30/s
30/s -12 = 30/s+8
(s)(30/s -12 ) = (s)(30/s+8 ) Cross multiply to cancel denominators
(s-8)(30 -12s) = (s-8)(30s/s+8 ) ==> 30s +240 -12s² -96s =30s Simplify:
(-1)(-12s² -96s +240 ) =0 ==> 12s² +96s -240 divide all by 12
s² + 8s -20 = 0 Factor and solve for s
(s +10)(s -2) =0 s-2=0 S= 2
Proof:
30/2 = 15 hours for original trip at 2mph,
increase speed by 8mph 2 + 8 = 10mph
30 miles at 10mph takes 3 hours; that is 12 hours less than his actual trip.
(Brainilest, please :-)
Answer: 0, 4, -9
Set the equation equal to zero.
x(x - 4)(x + 9) = 0
Solve for x by setting each factor equal to zero.
The factors in the equation are x, (x - 4), and (x + 9).
x = 4
x = -9
The zeros of the function are 0, 4, and -9.
Answer:
Hello! Here is your answer
Step-by-step explanation:
112=4(28)
a=4b
You can only have one variable so:
Combine b to a:
a-b=84
4b-b=84
Divide both sides by 3:
3b/3=84/3
b=28
But that is not it:
Sum of both cards:
a+b
a=112
b=28
112+28=140
= 140
I hope I was of help. If not please let me know! Thank you! Good luck!
