8x^2+6x^2+4x=138 combine like terms on left side
14x^2+4x=138 since the number of seats in the from row is just 4x, subtract 14x^2 from both sides
4x=138-14x^2 that would be the general solution, if you wanted the actual number you would have to solve for x and then multiply that value by 4 to know what "4x" is...
14x^2+4x-138=0
14x^2-42x+46x-138=0
14x(x-3)+46(x-3)=0
(14x+46)(x-3)=0
2(7x+23)(x-3)=0, since x>0
x=3 and thus
4x=12 seats
So there are 12 seats in the front row addition.
Outcome on winning = $100 - $20 = $80
Outcome on losing = $20
Probability of winning = 1/6
Probability of losing = 5/6
Expected Value = 1/6 (80) +5/6(-20) = -3.333
This shows on average from each game, the game earns $ 3.333.
So, if 1000 such games are played, the game will earn 1000 x 3.33 = $3330
So, the answer to this question is option A
I'll focus on problem 19 and problem 22
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Problem 19
Answers:
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Explanation:
The horizontal lines are parallel. Note the arrow markers along the interior portion of the lines. These similar markers tell us how the lines pair up to be parallel to one another.
Since the horizontal lines are parallel, this means the angles in question are congruent. They are corresponding angles.
x+15 = 102
x = 102-15
x = 87
Which leads to
x+15 = 87+15 = 102
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Problem 22
Answer: y = 27
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Explanation:
We have a pair of alternate exterior angles. They are congruent due to the parallel lines.
Let's solve for y.
7y-55 = 3y+53
7y - 3y = 53+55
4y = 108
y = 108/4
y = 27
Answer:
2
Step-by-step explanation:
2 km per trip x 2 trips = 4 km