Answer:
x=14 , y = 21
Step-by-step explanation:
y=x-7...............1
5x+2y=7......2
reset eqn .....2
2y=-5x+7
so; y=-x-7 ×5
2y=-5x+7 ×1
5y = -5x -35
2y = -5x +7
5y-2y = -5 + 5 -35-7
<u>3y</u> = - <u>42</u>
3 3
y = 14
sub y=14 into eqn ...........1
y = -x -7
14 = - x -7
14 +7 = - x
-21 = x
x = 14 , y =-21
Conditional probablility P(A/B) = P(A and B) / P(B). Here, A is sum of two dice being greater than or equal to 9 and B is at least one of the dice showing 6. Number of ways two dice faces can sum up to 9 = (3, 6), (4, 5), (4, 6), (5, 4), (5, 5), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 10 ways. Number of ways that at least one of the dice must show 6 = (1, 6), (2, 6), (3, 6), (4, 6), (5, 6), (6, 6), (6, 5), (6, 4), (6, 3), (6, 2), (6, 1) = 11 ways. Number of ways of rolling a number greater than or equal to 9 and at least one of the dice showing 6 = (3, 6), (4, 6), (5, 6), (6, 3), (6, 4), (6, 5), (6, 6) = 7 ways. Probability of rolling a number greater than or equal to 9 given that at least one of the dice must show a 6 = 7 / 11
Exactly 29.7, but you can't have 7/10 of a student so you round to 30. So 30 students are playing a music instrument because 330 times 0.09 is about 30
Answer:
x + 8
Step-by-step explanation:
x + 5 + 3.
add the numbers
↓
x + 8
X^2 -61 =20
X^2= 81x =9 x=-9