Answer:
Length = 18 in
Width = 15 in
Step-by-step explanation:
We have that the area of a rectangle is:
A = L * W
but L = 1.2 * W
A = 1.2 * (W ^ 2)
1.2 * (W ^ 2) = 270
(W ^ 2) = 270 / 1.2
W ^ 2 = 225
Therefore, W is equal to:
W = 225 ^ (1/2)
W = +/- 15, but only +15 makes sense
W = 15
Now for L:
L = 1.2 * 15
L = 18
A = 15 * 18 = 270 in ^ 2
Answer:
The area of the Iris is 4 times greater.
Step-by-step explanation:
Firstly, we have to realize that we cannot solve this problem without knowing the radius of the iris. because from the information given, the radius of the iris could well be the size of the galaxy and contract from width of 4mm to 2mm and we wouldn't know!
The average radius of the iris is 6mm, so we take this value.
Now, initially the width of the iris is 4mm, that means the radius of the pupil is:

Therefore it's area
is:

When the iris contracts to 2mm, the radius of the pupil becomes:

Then it's area is
:

To find how many times greater this final area is than the initial area, we just divide it by the initial area:

This is 4 times greater than the initial area.
Answer:
Step-by-step explanation:

use a calculator fo find the value
Answer:
8.
Denote the equation : y = ax + b
Use the first 2 values of x and y in table:
3a + b = 21
5a + b = 35
Subtract the 2 equations:
=> 2a = 14 => a = 7 => b = 21 - 3 x 7 = 0
=> The solution is y = 7x
9.
Denote the equation : y = ax + b
Use the first 2 values of x and y in table:
5a + b = 17
10a + b = 22
Subtract the 2 equations:
=> 5a = 5 => a = 1 => b = 17 - 5 x 1 = 17 - 5 = 12
=> The solution is y = x + 12
Hope this helps!
:)