Answer:
Since the 'base' and 'top' of any prism have the same shape, the surface area can be found by
surface area of prism = 2 * area of base + perimeter of base * H
So for the rectangular prism in your example..
surface area = 2LW + 2(L+W)H
= 2 * 7 * 4 + 2*(7+4)*5
= 56 + 2 * 11 * 5
= 56 +110
= 166 sq cm
Hope this helps
Answer:
Try retyping ,which expressions ..?? Maybe it didn't come out
Answer:
70
Step-by-step explanation:
the red lines mean the two sides are equal
so its an isosceles triangle meaning the two angles other than the 40° one are equal
the inner angles of a triangle must add up to 180
so 180-40 = 2x
140 = 2x
x = 140/2 = 70
Since they are similar both dimensions would have the same ratio. The ratio of 5 and 15 is 3. 15 is 3 times larger than 5, so the unknown dimension is 3 times larger than the known dimension.
3 x 10 = 30
The unknown dimension is 30
Answer:
5 hours 22 minutes
Step-by-step explanation:
Let us represent the number of hours that Jeri worked as: h
Jeri's lawn service charges an initial fee of $4.50 plus $3 an hour
= $4.50 + $3 × h
= $4.50 + 3h
If she is asked to start before 7 a.m. Jeri charges 1.5 times the regular amount.
= 1.5 × ($4.50 + 3h)
If she made $29.25 on a job that began at 5 am, how many hours did Jeri work?
Hence, we have the final equation;
= 1.5 × ($4.50 + 3h) = $29.25
= 6.75 + 4.5h = 29.25
Collect like terms
= 4.5h = 29.25 - 6.75
4.5h = 22.5
h = 22.5/4.5
h = 5.3571428571
Approximately= 5.36 hours
1 hour = 60 minutes
0.36 hour =
60 × 0.36
= 21.6 minutes
Approximately ≈ 22 minutes
Therefore, Jeri worked for 5 hours 22 minutes