Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
A function assigns the value of each element of one set to the other specific element of another set. The correct option is D.
<h3>What is a Function?</h3>
A function assigns the value of each element of one set to the other specific element of another set.
The time at which the ball will hit the ground is,
h(t) = −16t² + 10t + 6
0 = -16t² + 10t + 6
8t² - 8t + 3t - 3= 0
8t(t-1)+3(t-1) = 0
(8t+3)(t-1)=0
t = -0.375, 1
Hence, the ball hit the ground at 1 second, while the function in intercept form can be written as h(t) = (−8t − 3)(2t − 2).
Thus, the correct option is D.
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Variance of a continuous random variable X is defined as
Standard deviation is defined as

Hence standard deviation is the positive square root of variance.