The answer to the above question can be explained as under -
We know that, the sum of angles of triangle is 180°.
So, vertex angle plus base angles are equal are equal to 180°.
Let the vertex angle be represented by "v" and base angles be represented by "b".
Thus, v + b + b = 180°
So, v + 2b = 180°
Next, the question says, the vertex angle is 20° less than the sum of base angles.
Thus, 2b - 20° = v
<u>Thus, we can conclude that the correct option is A) v + 2b = 180°, 2b - 20° = v</u>
Answer:

Step-by-step explanation:
The perimeter of a polygon is equal to the sum of all the sides of the polygon. Quadrilateral PTOS consists of sides TP, SP, TO, and SO.
Since TO and SO are both radii of the circle, they must be equal. Thus, since TO is given as 10 cm, SO will also be 10 cm.
To find TP and SP, we can use the Pythagorean Theorem. Since they are tangents, they intersect the circle at a
, creating right triangles
and
.
The Pythagorean Theorem states that the following is true for any right triangle:
, where
is the hypotenuse, or the longest side, of the triangle
Thus, we have:

Since both TP and SP are tangents of the circle and extend to the same point P, they will be equal.
What we know:
Thus, the perimeter of the quadrilateral PTOS is equal to 
Answer:
The three-dimensional surface represented by the equation x+y=2 is an inclined plane, as seen in the image.
Answer:
60
Step-by-step explanation:
10 + 5 = 15. 15/2 is 7.5. 7.5 times 8 is 60. The formula for the area of the trapezoid is (a+b)/2 x h.