Answer:
Step-by-step explanation:
3x and 3y are not "like terms," despite having the same coefficient.
Like terms have the same variable. For example, 3x and 2x are like terms, so
3x+2x = 5x
Answer: 30
Step-by-step explanation:
21+39/2
=30
Each container is 50 pounds, forget about the second sentence it's just there to confuse you. One ton is 2,000 pounds, half of that is 1,000 lbs. 1,000 divided by 20 is 50. 50 pounds each.
The hardest part is finding the length of the curve at the top. To find arc length, multiply the circumference by the arc angle divided by full angle (360°) in a circle. Or:

x, the arc angle in a semicircle, is 180°.
r, the radius is 7/2 = 3.5.
Now just plug the numbers in and solve for arc length, s.
s = 2π(3.5)(1/2) ≈ 11.00
Now just add up all the sides. 11cm + 10cm + 10cm + 7cm = 38 cm.