X+8
2x
x-3
8 more hours
twice the number
3 years younger
Answer:
Step-by-step explanation:
Answer:
a. (2,5)
b. (14,15.5)
Step-by-step explanation:
a.
y=4x-3
y=-2x+9
Set both equations equal to each other to solve for x.
4x-3=-2x+9
6x=12
x=2
Plug in x to solve for y.
y=4x-3
y=4(2)-3
y=8-3
y=5
(2,5)
b.
y=(5/4x)-2
y=(-1/4x)+19
Set both equations equal to each other to solve for x.
(5/4x)-2=(-1/4x)+19
4((5/4x)-2=(-1/4x)+19)
5x-8=-x+76
6x=84
x=14
Plug in x to solve for y.
y=(5/4x)-2
y=(5/4(14))-2
y=17.5-2
y=15.5
(14,15.5)
We can build a system of two linear equations with two unknowns with the info provided in the problem, one with Kelsey info and one with Mitch info like so:
Lets call p the amount on peak minutes and n the amount of non-peak minutes:
45p + 50n = 27.75
70p + 30n = 36
lets reduce the equations dividing the first by 5:
9p + 10n = 5.55
<span>70p + 30n = 36
</span>now, to eliminate n, lets multiply the first equation by -3 and add the two equations:
-27p - 30n = -16.65
<span>70p + 30n = 36
</span>----------------------------
43p + 0 = 19.35
p = 19.35<span>/43
p = 0.45
therefore the peak rate is $0.45 per minute
lets substitute in one of the original equations this result:
</span><span>45p + 50n = 27.75
</span>45(0.45) + 50n = 27.75
20.25 <span>+ 50n = 27.75
50n = 27.75 - 20.25
50n = 7.5
n = 7.5/50
n = 0.15
therefore the non-peak rate per minute is $0.15</span>
Answer:
Balance is $260.
Step-by-step explanation:
4% of $250
= 0.04 * 250
= $10.
250 + 10 = $260.
