She needs to earn at least 84 to buy the mp3 player
earnings=earningsperhour times numberofhoursworked
earnings per hour=12 dollars
number of hoursworked=h
therefor
earnings=12 ties h or12h
earnings is at least 84
earnings is greater than or equal to 84
earnings<u>></u>84
12h<u>></u>84
solve
12h<u>></u>84
divide both sides by 12
h<u>></u>7
she needs to work at least 7 hours
to graph, draw a line at x=0 and shade to the right, make the line solid
Answer:
Henry's balloon was farther from the town at the beginning and Henry's balloon traveled more quickly.
Step-by-step explanation:
The distance of Tasha's balloon from the town is represented by the function y = 8x+ 20 ............. (1)
Where y is the distance in miles from the town and x represents the time of fly in hours.
So, at the start of the journey i.e. at x = 0, y = 20 miles {From equation (1)} from the town.
Again, Tasha's balloon is traveling at a rate of 8 miles per hour.
Now, Henry's balloon begins 30 miles from the town and is 48 miles from the town after 2 hours.
So, Henry's balloon traveling with the speed of miles per hour.
Therefore, Henry's balloon was farther from the town at the beginning i.e. 30 miles from the town. And Henry's balloon traveled more quickly i.e at the rate of 9 miles per hour.
3s + 4j = 360
1s + 3j = 220
This one we can solve using substitution, in that
s + 3j = 220 implies s = 220 - 3j (subtract 3j from each side).
Now substitute into the first equation:
3(220 - 3j) + 4j = 360. Solve for jackets.
660 - 9j + 4j = 360 [Distributive property]
660 - 5j = 360 [Add -9j + 4j]
Subtract 360 from each side, and add 5j to each side.
660 - 360 - 5j + 5j = 360 - 360 + 5j
300 = 5j
Divide each side by 5.
$60 = price of a jacket.
Three of these plus a shirt runs $220.
3(60) = 180
180 + s = 220
180 - 180 + s = 220 - 180 [Subtract 180 from each side]
s = 40
Now we double check.
3(40) + 4 (60) = 120 + 240 = 360. This satisfies the first equation.
We could check the second one too, but I'm satisfied.
Answer:
n = 60.22
Step-by-step explanation:
Hello
To find Sn, we need to draw out equations for each a₇ and a₁₉
In an arithmetic progression,
Sn = a + (n-1)d
Where Sn = sum of the A.P
a = first term
d = common difference
a₇ = 32
32 = a + (7-1)d
32 = a + 6d ........equation (i)
a₁₉ = 140
140 = a + (19-1)d
140 = a + 18d .........equation (ii)
Solve equation (i) and (ii) simultaneously
From equation (i)
32 = a + 6d
Make a the subject of formula
a = 32 - 6d .....equation (iii)
Put equation (iii) into equation (ii)
140 = (32 - 6d) + 18d
140 = 32 - 6d + 18d
Collect like terms
140 - 32 = 12d
12d = 108
d = 108 / 12
d = 9
Put d = 9 in equation (i)
32 = a + 6(9)
32 = a + 54
a = 32 - 54
a = -22
When Sn = 511
Sn = a + (n - 1)d
Substitute and solve for n
511 = -22 + (n-1) × 9
511 = -22 + 9n - 9
511 = -31 + 9n
511 + 31 = 9n
542 = 9n
n = 542 / 9
n = 60.22
