Answer:
5 cm
Step-by-step explanation:
If AB is tangent to the circle k(O), then radius OB is perpendicular to segment AB.
If BC is tangent to the circle k(O), then radius OC is perpendicular to segment AC.
Consider two right triangles ABO and ACO. In these triangles:
- AO is common hypotenuse;
- ∠OBA=∠OCA=90°, because AB⊥OB, AC⊥OC;
- OB=OC as radii of the circle k(O).
By HL theorem, triangles ABO and ACO are congruent. Then
- ∠OAB=∠OAC=30°;
- AC=AB=5 cm.
Hence, ∠BAC=∠OAB+∠OAC=30°+30°=60°.
Consider triangle ABC, this triangle is isosceles triangle. In isosceles triangles angles adjacent to the base are congruent, thus
∠CBA=∠BCA=1/2(180°-60°)=60°.
Therefore, triangle ABC is an equilateral triangle, so BC=AB=AC=5 cm.
Answer:
The average rate of change of f(t) from t = 3 seconds to t = 5 seconds is -80 feet per second.
Step-by-step explanation:
The function that models the height of the ball is:

At t=3, 
At t=5, 
The average rate of change is simply the slope of the secant line connecting.
and
.
The average rate of change



The answer is C, because to find IQR you have to find the difference (subtract) of the first and third quartile
There are three steps
1 rearrange the equation so "y" is on the left and everything else is on the right
2 plot the "y=" line (make it a solid line for y< or y> and a dashed line for y< or y>)
3 shade above the line for a "greater than" (y> or y>) line under that or below the line for a less than (y< or y< line under it)