Answer:
find 9% of 12
12 times 9 divided by 100
108/100
$1.08
12+1.08
Your mean costs $13.08
-Have a nice meal!
Answer:
4n +28
Step-by-step explanation:
Tommy's purchases add up to ...
4n +10 + 18 = 4n +28
T=time
d=st
r=train speed
p=plane speed
<span>160=rt
</span><span>720=pt
speed of plan is 20kmph less than 5 times speed of train
p=5r-20
we notice that 160 times 4.5=720
times first equaton by 4.5
720=4.5rt
720=pt
set equal
4.5rt=pt
divide both sides by t
4.5r=p
sub </span><span>p=5r-20 for p
4.5r=5r-20
minus 4.5r from both sides
0=0.5r-20
add 20 to both sides
20=0.5r
times 2 both sides
40=r
sub back</span><span>
p=5r-20
p=5(40)-20
p=200-20
p=180
plane is 180kmph
train is 40kmph
</span>
Answer:
15
Step-by-step explanation:
Answer:
width = 8 feet and length = 12 feet
Step-by-step explanation:
Let the width be w then the length = 3w - 12 ( 12 less than 3 times the width )
The area (A) of a rectangle is
A = length × width, that is
w(3w - 12) = 96 ← area of floor
3w² - 12w = 96 ( subtract 96 from both sides )
3w² - 12w - 96 = 0 ← in standard form for a quadratic equation
Divide all terms by 3
w² - 4w - 32 = 0
Consider the product of the factors of the constant term ( - 32) which sum to give the coefficient of the w- term (- 4)
The factors are - 8 and + 4, since
- 8 × 4 = - 32 and - 8 + 4 = - 4, hence
(w - 8)(w + 4) = 0
Equate each factor to zero and solve for w
w - 8 = 0 ⇒ w = 8
w + 4 = 0 ⇒ w = - 4
However, w > 0 ⇒ w = 8
Hence width = 8 feet
length = 3w - 12 = (3 × 8) - 12 = 24 - 12 = 12 feet
