2x - 10 = 30
2x = 40
x = 20
Answer: 10
Step-by-step explanation: subtract 5 by 45 to get 40 then divide 4 to get 10
Answer:
- 525 = (w+4)(w)
- 21 ft by 25 ft
Step-by-step explanation:
Let w represent the width of the floor. Then the length of the floor is (w+4) and its area is ...
A = LW
525 = (w+4)(w)
w^2 +4w -525 = 0
(w -21)(w +25) = 0 . . . . factor the above
Solutions are ...
w = 21, w = -25
We are interested in the positive solution: w = 21.
The floor is 21 feet wide and 25 feet long.
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<em>Alternate solution</em>
Sometimes, when the factors aren't obvious, it works well to write an equation for the average of the dimensions. Here, we can represent that with x, and use (x-2) for the width, and (x+2) for the length. Then we have ...
525 = (x-2)(x+2) = x^2 -4
529 = x^2
√529 = 23 = x
Then w=23 -2 = 21, and the length is w+4 = 25.
The report was 10 pages. This is because we know that Jason wrote half a page a day, and if he consistently wrote each day and I took him a total of 20 days to finish, all you would have to do is multiply 20 by .5 (half a page), you would then get 10, which means that in 20 days he wrote 10 pages
Answer:
10000π units²
Step-by-step explanation:
From the question given above, the following data were obtained:
Circumference (C) = 100π
Surface Area of sphere (SA) =?
Next, we shall determine the radius. This can be obtained as follow:
Circumference (C) = 100π
Radius (r) =?
C = 2πr
100π = 2πr
Divide both side by 2π
r = 100π / 2π
r = 50 units
Finally, we shall determine the surface area of the sphere. This can be obtained as follow:
Radius (r) = 50 units
Surface Area of sphere (SA) =?
SA = 4πr²
SA = 4 × π × 50²
SA = 4 × π × 2500
SA = 10000π units²
Therefore, the surface area of the sphere is 10000π units²