Answer:
a = -2
b = 1
c = 5
Step-by-step explanation:
Given:
2a + 4b + c = 5 ............(1)
a - 4b = - 6
or
a = 4b - 6 .............(2)
2b + c = 7
or
c = 7 - 2b ...........(3)
substituting 2 and 3 in 1, we get
2(4b - 6 ) + 4b + (7 - 2b) = 5
or
8b - 12 + 4b + 7 - 2b = 5
or
10b - 5 = 5
or
b = 1
substituting b in 2, we get
a = 4(1) - 6
or
a = -2
substituting b in 3, we get
c = 7 - 2(1)
or
c = 5
thus,
a = -2
b = 1
c = 5
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 :-)
I think the answer is:
X=3
Y=-2
Answer:
226 dollars
Step-by-step explanation:
Bryan = 176
Jamie = 88
Nancy = 226
