Answer:
7z
Step-by-step explanation:
Answer:
Explanation:
x - 7y = 7
-7y = -x + 7
y = (-1/-7)x + 7/-7
y = (1/7)x - 1
6x - 7y = -28
-7y = -6x - 28
y = (-6/-7)x - 28/-7
y = (6/7)x + 4
Answer:
x = 15
Step-by-step explanation:
We assume you want to find the value of x.
Know (or prove) that in this geometry, all of the right triangles are similar. That means the ratios of corresponding sides are proportional.
short side / hypotenuse = 9/x = x/25
x^2 = (9)(25) . . . . . . . . . . multiply by 25x ("cross multiply")
x = √((9)(25)) = (3)(5) . . . take the square root
x = 15
Answer: 15/91 which is choice B
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There are two methods to find this answer.
Method 1) We have 6 girls and 8+6 = 14 students. The probability of picking a girl is 6/14 = 3/7. After the first girl is chosen, we have 5 girls left out of 14-1 = 13 students overall. The probability of picking another girl (assuming the first selection was a girl) is 5/13. Multiply these probabilities: (3/7)*(5/13) = (3*5)/(7*13) = 15/91
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Method 2) We can use the nCr combination formula. Order does not matter.
We have nCr = 6 C 2 = 15 ways to pick 2 girls. See the attached image below for the steps (figure 1)
Out of nCr = 14 C 2 = 91 ways to pick 2 students. See the attached image below for the steps (figure 2)
So that's another way to get the answer 15/91.