Certain because the papers are labeled from 1 - 12, thus you will always pick out a number less than 15.
SU would be the hypotenuse so you can use Pythagorean Theorem to solve this problem.
42^2 + 56^2 = c^2
1764 + 3136 = c^2
4900 = c^2
70 = c
The "20" under <em>n</em> means "When <em>n</em> is 20,". Therefor, on the other side of the table, 5n-2 would be 5(20)-2. 5*20=100, 100-2 is 98. The top missing value is 98.
For the other side, it's saying that 5n-2 is 38. You have to work backwards to get your answer. The opposite of -2 is 2, so 38 + 2 is 40. The opposite of *5 is /5, so 40/5 is 8. The bottom missing value is 8.
Answer: Choice C) -11
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Explanation:
The first equation given is y = 3 - 1/2x
In other words, y is the same as 3 - 1/2x.
We can replace y in the second equation with 3 - 1/2x
This is known as substitution (think of a substitute teacher who is a temporary replacement for your teacher)
Doing this leads to...
3x+4y = 1
3x+4*y = 1
3x+4*( y ) = 1
3x+4*( 3 - 1/2x ) = 1 <<--- y has been replaced with 3-1/2x
3x+4*(3) +4*(-1/2x) = 1
3x+12-2x = 1
3x-2x+12 = 1
x+12 = 1
x+12-12 = 1-12 <<-- subtracting 12 from both sides
x = -11
Which is why the answer is choice C) -11
