Answer:
A 90
Step-by-step explanation:
multiple ways to prove this.
e.g. since the angle between the two lines from the center of the circle to the 2 tangent touching points is 90 degrees (that is the meaning of these 90 degrees here as the angle of the circle segment defined by the 2 tangent touching points and the circle center), the tangents have the same "behavior" as tan and cot = the tangents at the norm circle at 0 and 90 degrees. they hit each other outside of the circle again at 90 degrees.
another way
imagine the two right triangles of the tangents crossing point to the circle center and the tangent/circle touching points.
the Hypotenuse of each triangle is cutting the 90 degree angle of the circle segment exactly in half (due to the symmetry principle). so the angle between radius side and Hypotenuse is 90/2 = 45 degrees.
that means also the angle of such a right triangle at the tangent crossing point is 45 degrees (as the sum of all angles in a triangle must be 180, we have the remainder of 180 - 90 - 45 = 45 degrees).
the angles of both right triangles at that point are the same, and so we can add 45+45 = 90 degrees for the total angle at the tangent crossing point.
-x+3x=2x
2x=2+6
2x=8
8/2=4
x=4
Answer:
20a³
Step-by-step explanation:
Simply multiply:
-5(-4) = 20
-a(-a)(a) = a²(a) = a³
20a³
The formula used to find the length of a line segment is the same formula as the Pythagoras theorem.
We take CD as the hypotenuse of the right-angled triangle and the distance between the x-coordinates and y-coordinates as the length of two short sides.
We can write the formula as
CD =

CD =
Answer:
Change in sulfur oxide in the air =
Step-by-step explanation:
Data provided in the question:
Relation between the amount of sulfur oxide in the air and the population as:
S² = 110P² + 20P + 600
Population growth rate,
= 10 people per month
Now,
change in sulfur oxide with time i.e 
differentiating the given relation with respect to time 't'
we have
=
+ 20
at P = 100 and
= 10 people per month
we have
= 2 × 110 × 100 × 10 + 20
or
= 220020
or
=
or
Change in sulfur oxide in the air =