Two tangents drawn to a circle from a point outside it, are equal in length.prove it.
1 answer:
Given: A circle with centre O; PA and PB are two tangents to the circle drawn from an external point P.
To prove: PA = PB
Construction: Join OA, OB, and OP.
It is known that a tangent at any point of a circle is perpendicular to the radius through the point of contact.
OA⊥PA
OB⊥PB
In △OPA and △OPB
∠OPA=∠OPB (Using (1))
OA=OB (Radii of the same circle)
OP=OP (Common side)
Therefor △OPA≅△OPB (RHS congruency criterion)
PA=PB
(Corresponding parts of congruent triangles are equal)
Thus, it is proved that the lengths of the two tangents drawn from an external point to a circle are equal.
The length of tangents drawn from any external point are equal.
So statement is correct
To prove: PA = PB
Construction: Join OA, OB, and OP.
It is known that a tangent at any point of a circle is perpendicular to the radius through the point of contact.
OA⊥PA
OB⊥PB
In △OPA and △OPB
∠OPA=∠OPB (Using (1))
OA=OB (Radii of the same circle)
OP=OP (Common side)
Therefor △OPA≅△OPB (RHS congruency criterion)
PA=PB
(Corresponding parts of congruent triangles are equal)
Thus, it is proved that the lengths of the two tangents drawn from an external point to a circle are equal.
The length of tangents drawn from any external point are equal.
So statement is correct
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Answer:
The graph is shown below.
Step-by-step explanation:
Given:
The inequality of a line to graph is given as:
In order to graph it, we first make the 'inequality' sign to 'equal to' sign. This gives,
Now, we plot this line on a graph. The given line is of the form:
Where, 'm' is the slope and 'b' is the y-intercept.
So, for the line ,
The y-intercept is at (0, -3).
In order to draw the line correctly we find another point. Let the 'y' value be 0.
Now,
So, the point is (3, 0).
Now, we mark these points and draw a line passing through these two points.
Now, consider the line inequality . The 'y' value is less than
. So, the solution region will be region below the line and excluding all the points on the line. So, we draw a broken line and shade the region below it.
The graph is shown below.
9 days ago, the mold covered an area of .
Today (after 9 days), the mold covers an area of .
<em>What is the increase in area?</em> It went from 3 to 9. So the increase is .
Now, we need to find <em>rate of change</em>. It means to find how much the area increased every day over the past 9 days. We simply divide <em>the increase (6)</em> by the <em>total number of days (9)</em> to find the rate per day. So we have,
ANSWER: Change of Rate = per day