Answer:
Since pair of opposite sides are parallel and adjacent sides meets at right angles, the quadrilateral COAT is a rectangle.
Step-by-step explanation:
The vertices of the given quadrilateral is 
It is sufficient to show that pair of opposite sides are parallel and adjacent sides are perpendicular.
The slope of each side can be found using the formula;

Slope of CO,

A line with a zero slope is a horizontal line.
The slope of OA,

This slope is undefined.
A line with an undefined slope is a vertical line.
This shows that,the side CO and OA of the quadrilateral meets at right angle.
The slope of AT,

This is also a horizontal line.
The slope of TC,

This also a vertical line.
This implies that, side TC and side AT meets at Tat right angles and TC is parallel to OA.
Also AT is parallel to TO.
This shows that COAT is a rectangle.
Answer:
a:c = 35:24
a:c = 20:27
a:c = 35:22
a:c = 28:27
Step-by-step explanation:
a:b = 7:3
Using cross products
3a = 7b
Divide by 7
3a/7 = b
Now we want
8b = 5c
Substitute in 3a/7 for b
8 (3a/7) = 5c
24/7a = 5c
Multiply by 7
24/7a *7 = 5*7c
24a = 35c
Divide by c
24 a/c = 35
Divide by 24
a/c = 35/24
a:c = 35:24
a:b = 4:9
Using cross products
9a = 4b
Divide by 4
9a/4 = b
Now we want
3b = 5c
Substitute in 9a/4 for b
3 (9a/4) = 5c
27/4a = 5c
Multiply by 4
27/4a *4 = 5*4c
27a = 20c
Divide by c
27 a/c = 20
Divide by 27
a/c = 20/27
a:c = 20:27
b:c = 5:11
Using cross products
11b = 5c
Divide by 11
b = 5c/11
Now we want
2a = 7b
Substitute in 5c/11 for b
2a = 7(5c/11)
2a = 35c/11
Multiply by 11
2a*11 = 35c
22a = 35c
Divide by c
22 a/c = 35
Divide by 22
a/c = 35/22
a:c = 35:22
b:c = 14:3
Using cross products
3b = 14c
Divide by 3
b = 14c/3
Now we want
9a = 2b
Substitute in 14c/3 for b
9a = 2(14c/3)
9a = 28c/3
Multiply by 3
9a*3 = 28c
27a = 28c
Divide by c
27 a/c = 28
Divide by 27
a/c = 28/27
a:c = 28:27
Answer:
1.38 * 10^ -2
Step-by-step explanation:
.0138
We need 1 number to the left of the decimal
1.38 * 10^ something
We moved it 2 places to the right, that means our exponent is -2. If we had moved it to the left, our exponent would have been positive
1.38 * 10^ -2
The answer to your question is 2 and 4.