If you would like to solve the system of equations, you can do this using the following steps:
4x^2 + 9y^2 = 72
2x - y = 4 ... 2x - 4 = y
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<span>4x^2 + 9y^2 = 72
</span><span>4x^2 + 9 * (2x - 4)^2 = 72
</span>4x^2 + 9 * (4x^2 - 16x + 16) = 72
4x^2 + 36x^2 - 144x + 144 = 72
40x^2 - 144x + 144 - 72 = 0
40x^2 - 144x + 72 = 0
10x^2 - 36x + 18 = 0
5x^2 - 18x + 9 = 0
(5x - 3) * (x - 3) = 0
1. 5x - 3 = 0 ... 5x = 3 ... x = 3/5
2. x = 3
<span>1. y = 2x - 4 = 2 * 3/5 - 4 = 6/5 - 20/5 = -14/5
2. y = 2x - 4 = 2 * 3 - 4 = 6 - 4 = 2
1. (x, y) = (3/5, -14/5)
2. (x, y) = (3, 2)
The correct result would be </span>(3/5, -14/5) and <span>(3, 2).</span>
They aren't independent since the probability uses all the cards in the deck
So at the first deal we have the chance of 26/52 of getting a red card, at the second deal we have the chance of a 25/51 of getting another red card, so they aren't independent
There are 120 different possible groups.
(10 * 9 * 8)/(3 * 2 * 1) + 120
Answer: Option <span>C. To get system B, the second equation in system A was replaced by the sum of that equation and the first equation multiplied by -3. The solution to system B will be the same as the solution to system A.
First equation of system A multiplied by -3:
(-3)(x+6y=5)
(-3)(x)+(-3)(6)=(-3)(5)
-3x-18=-15
Sum of the second equation of system A and the first equation multiplied by -3:
(-3x-18)+(3x-7y)=(-15)+(-35)
-3x-18+3x-7y=-15-35
-25y=-50
System B
x+6y=5
-25y=-50 </span>
It would either be 21 or 25 as they both have the same amount of factors :)
