Answer:
Choice A
1/17; no, they are dependent events
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Explanation:
There are 13 spades and 52 cards total. So 13/52 = 1/4 is the probability of drawing one spade
If we do not replace the card we pull out, then the probability of another spade is 12/51 since there are 12 spades left out of 51 total.
Multiply the fractions 1/4 and 12/51 to get
(1/4)*(12/51) = (1*12)/(4*51) = 12/204 = 1/17
The two events are not independent because the second event (pulling out a second spade) depends entirely on what happens in the first event (pulling out a first spade). The fact that the probability is altered indicates we have dependent events.
Just work backwards.
342.5/ 34.25 = 10
X² + 8x +y² - 2y -64 =0
We see that the equation has x² and y² . Also we see that coefficients in front of x² and y² are equal. So this is an equation of the circle.
(x² + 8x) +(y² - 2y) -64 =0
(x² + 8x) +(y² - 2y) = 64
We need to complete square for x and y groups, that means it should be written in form (a+b)² or (a-b)².
Expressions in parenthesis we will write as a²+/-2ab+b², to write it after as (a+/-b)², because a²+/-2ab+b² = (a+/-b)²
(x² + 2*4x) +(y² - 2*1y) = 64
(x² + 2*4x+4²) +(y² - 2*1y+1²) = 64+4²+1²
(x+4)² + (y-1)²= 81 Sometimes this is called a standard form of the circle.
(x+4)² + (y-1)²= 9² Sometimes it is required to write like this.
And if you are studying circles,ellipses and hyperbolas, the standard form should look like