Answer:
2.17ft/s
Step-by-step explanation:
Look at the sketch of ladder at the beginning and after 3 seconds it starts to fall,
Distance of ladder from the wall 3 seconds after ladder starts to fall = Initial distance+ Velocity× time
= 6 + 2×3
= 12ft
Use trignometry to find out the speed of the top of ladder
cosθ= 12/20
θ= 0.825 rad
tan θ= v/2
v= 2.17ft/s
Given:
A right prism has height 7½ and triangular bases with sides of length 5, 12, and 13.
To find:
The total surface area of the prism.
Solution:
We have,
Height of prism = 7½ = 7.5
Sides of triangular base are 5, 12, 13. These sides of Pythagorean triplets because



So, the base of the prism is a right triangle.
Area of a triangle is



The area of the base is equal to the area of the top, i.e.,
sq units.
Perimeter of the base is


The curved surface area of the prism is



Now, the total area of the prism is



Therefore, the total surface area of the triangular prism is 285 square units.
The correct answer is the second from the top.
Answer: If we define 2:00pm as our 0 in time; then:
at t= 0. the velocity is 30 mi/h.
then at t = 10m (or 1/6 hours) the velocity is 50mi/h
Then, if we think in the "mean acceleration" as the slope between the two velocities, we can find the slope as:
a= (y2 - y1)/(x2 - x1) = (50 mi/h - 30 mi/h)/(1/6h - 0h) = 20*6mi/(h*h) = 120mi/
Now, this is the slope of the mean acceleration between t= 0h and t = 1/6h, then we can use the mean value theorem; who says that if F is a differentiable function on the interval (a,b), then exist at least one point c between a and b where F'(c) = (F(b) - F(a))/(b - a)
So if v is differentiable, then there is a time T between 0h and 1/6h where v(T) = 120mi/
Answer:
Step-by-step explanation:
The discriminant is used to determine the number and nature of the zeros of a quadratic. If the discriminant is positive and a perfect square, there are 2 rational zeros; if the discriminant is positive and not a perfect square, there are 2 rational complex zeros; if the discriminant is 0, there is 1 rational root; if the discriminant is negative, there are no real roots.
The roots/solutions/zeros of a quadratic are where the graph goes through the x axis. Those are the real zeros, even if they don't fall exactly on a number like 1 or 2 or 3; they can fall on 1.32, 4.35, etc. They are still real. If the graph doesn't go through the x-axis at all, the zeros are imaginary because the discriminant was negative and you can't take the square root of a negative number. As you can see on our graph, the parabola never goes through the x-axis. Therefore, the zeros are imaginary because the discriminant was negative. Choice C. Get familiar with your discriminants and the nature of quadratic solutions. Your life will be much easier!