Suppose the one's digit is x, the ten's digit is y. the original number is 10y+x, the reversed number is 10x+y
x+y=13
(10x+y)=(10y+x)-9 =>9y-9x=9 =>y-x=1
Add the two equation to solve: 2y=14 =>y=7
x=13-7=6
the original number is 76.
This is the concept of trajectories;
We are required to calculate the time taken for the base ball whose distant to reach the maximum height has been modeled by h=-16t^2+64t+4.2 took to hit the ground. Here we proceed as follows;
At the time when the base ball hits the ground the height,h=0
Thus;
-16t^2+64t+4.2=0
this is a quadratic equation, to solve the quadratic equation we use the formula;
t=[-b+/- sqrt(b^2-4ac)]/(2a)
where;
a=-16,b=64, c=4.2
thus substituting the values in our formula we get:
t=[-64+/-sqrt(64^2-4*(-16)*4.2)]/(-16*2)
t=[-64+/- sqrt(4364.8)]/(-32)
t=[-64+/-66.1]/(-32)
t=4.1 or-0.1
thus the we take the positive value t=4.1 and we conclude that the time taken for the ball to hit the ground was 4.1 seconds
Answer:
15%
Step-by-step explanation:
set up 15/20= x/100
cross multiply to solve for x
1500=20x
x= 75
15 dollars is 75% of the original price, so there was a 15% change
Answer:
(A) At the intersection of the first line with the third line, the bottom left angle is 115 degrees. At the intersection of the second line with the third line, the uppercase left angle is 65 degrees.
Step-by-step explanation:
Alternate interior angles are supplementary when parallel lines are crossed by a transversal. The first description seems to be describing alternate interior angles. (See attachment)
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<em>Comment on orientation</em>
If the transversal is oriented horizontally, then the descriptions of the angles will be of different angles than assumed here.
