52/4 = 13
$13 = 1 hour.
$6.50 = halfhour
13 x 3 = $39
She would have to work for 3 hours to earn $39
Answer:
v
Step-by-step explanation:
7.) Area of a square pyramid is given by A = s^2 + 2sl; where s is the side length of the base and l is the slant height.
Area of given pyramid = 4^2 + (2 x 4 x 7) = 16 + 56 = 72 ft^2
8.) Area of the given pyramid is the area of the hexagonal base plus the area of the six slant triangles.
Area of hexagonal base = (3sqrt(3))/2 x 10^2 = 150 x 1.732 = 259.8
Area of the 6 traingles = 6(1/2 x 10 x 13) = 6 x 65 = 390
Total surface area of the pyramid = 259.8 + 390 = 649.8 ≈ 650 m^2
9.) Using pythagoras rule, the slant height is sqrt(6^2 + 3.5^2) = sqrt(36 + 12.25) = sqrt(48.25) = 6.9 mm
10.) The surface area of a cone is given by πr^2 + πrl
Area = π x 6^2 + π x 6 x 20 = 36π + 120π = 490.1 cm^2
11.) l = sqrt(r^2 + h^2) = sqrt(11^2 + 16^2) = sqrt(121 + 256) = sqrt(377) = 19m
It looks like this
. So the answer is <span>
A) 1.2 in. by 1.2 in.</span>
I'd suggest using "elimination by addition and subtraction" here, altho' there are other approaches (such as matrices, substitution, etc.).
Note that if you add the 3rd equation to the second, the x terms cancel out, and you are left with the system
- y + 3z = -2
y + z = -2
-----------------
4z = -4, so z = -1.
Next, multiply the 3rd equation by 2: You'll get -2x + 2y + 2z = -2.
Add this result to the first equation. The 2x terms will cancel, leaving you with the system
2y + 2z = -2
y + z = 4
This would be a good time to subst. -1 for z. We then get:
-2y - 2 = -2. Then y must be 0. y = 0.
Now subst. -1 for z and 0 for y in any of the original equations.
For example, x - (-1) + 3(0) = -2, so x + 1 = -2, or x = -3.
Then a tentative solution is (-3, -1, 0).
It's very important that you ensure that this satisfies all 3 of the originale quations.
