Let's say Jackson's age now is x.
In 20 years, (so 20+x), Jackson seven years ago will be 2/5ths of that age.
So 2/5(20+x)=x-7
Then you solve the equation
8+2/5x=x-7
15=3/5x
x=25
Jackson is 25 years old.
Let's check our answer! In 20 years, Jackson will be 45. 7 years ago, he was 18. 2/5 of 45 is 18. Our answer is correct!
Answer:
1,809.98 lb*m/s^2
Step-by-step explanation:
First, we want to know how much weight of the boulder is projected along the path in which the boulder can move.
The weight of the boulder is:
W = 322lb*9.8 m/s^2 = (3,155.6 lb*m/s^2)
This weight has a direction that is vertical, pointing downwards.
Now, we know that the angle of the hill is 35°
The angle that makes the direction of the weight and this angle, is:
(90° - 35°)
(A rough sketch of this situation can be seen in the image below)
Then we need to project the weight over this direction, and that will be given by:
P = W*cos(90° - 35°) = (3,155.6 lb*m/s^2)*cos(55°) = 1,809.98 lb*m/s^2
This is the force that Samuel needs to exert on the boulder if he wants the boulder to not roll down.
Partial Answer:
For #10 the solutions are 2 and 5
Step-by-step explanation:
Solutions for an equation can be x-intercepts, or where it touches the x or horizontal line. The equation in #10 touches the x line at 2 and 5.
Answer:
50/50
Step-by-step explanation:
2 is half of 4. 4/2 is 50/50
The surface area of a cylinder is the sum of the area of the two ends and the lateral area.
.. surface area = 2*(end area) +(lateral area)
.. = 2*(π*r^2) +(2π*r*h)
.. = 2π*r*(r +h)
.. = 2*3.14*(8 in)*(8 in +8 in)
.. = 3.14*256 in^2
.. ≈ 803.8 in^2
The 3rd selection is appropriate.