The formula of an area of a rectangle:
A = wl
We have l = w - 4 and A = 21.
Substitute:
w(w - 4) = 21 <em>use distributive property</em>
(w)(w) + (w)(-4) = 21
w² - 4w = 21 <em>subtract 21 from both sides</em>
w² - 4w - 21 = 0
w² - 7w + 3w - 21 = 0
w(w - 7) + 3(w - 7) = 0
(w - 7)(w + 3) = 0 ↔ w - 7 = 0 ∨ w + 3 = 0
w = 7 ∨ w = -3 < 0
l = w - 4 → l = 7 - 4 = 3
<h3>Answer: the length = 3 u.</h3>
Answer:
a
Step-by-step explanation:
Answer: Time at which the meet = 10:17:24 am
Step-by-step explanation: Speed of Ivan = 12 mph
Speed of Kate = 16 mph
Total distance traveled = Initial separation = 40 miles
Ivan leaves his house at 8:00 a.m and Kate leaves her house at 9:30 a.m
If t is the time of catch up after Ivan starting, time taken by Kate is t - 1.5,
We have
Distance = Speed x Time
Total distance traveled = Distance traveled by Kate + Distance traveled by Ivan
40 = t x 12 + (t-1.5) x 16
40 = 28t - 24
28t = 64
t = 2.29 hours
So after 2.29 hours of Ivan's starting they meet,
Time = 8:00 am + 2.29 hours = 10:00 am + 0.29 x 60 minutes = 10:17am + 0.4 x 60 seconds = 10:17:24 am
Time at which the meet = 10:17:24 am
Answer:
Step-by-step explanation:
12/3=4
4 divided by 17/18 equals to 4* 18/17=72/17= 4 4/17
Thus the answer is 4 4/17