1(x + 3) + 3(x - 1) = 20
1(x) + 1(3) + 3(x) - 3(1) = 20
x + 3 + 3x - 3 = 20
x + 3x + 3 - 3 = 20
4x = 20
4 4
x = 5
It doesnt make any sense because the diagram is wrong so I'm guessing it would be either 8 or 6. Im sorry that problem is wrong :(
Answer:
1. {0, 1/5, 2/5}
Step-by-step explanation:
all other answers have a 2 in them and 5(2)+2 is 12 so it wouldn't be less than 10
Answer:
(6)(3)+(18+6x)
Step-by-step explanation:
6 times 3 will give you the area of the table without the extension and the problem says that (18+6x) is the area for the extension. So when you add up the two areas you get the total area!
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.