Answer:
5x=90 x=90/5=18. So, the answer is 18.
Answer: a) 3 and -3 b) 4 and 2
c) 3.5 and 2.5 d) 5.5 and 0.5 e) This is due to the difference in the coefficient of (x-3)² and the value at the right side of each equation.
Step-by-step explanation:
a) 3x²-9 = 0
3x² = 0+9
3x² = 9
Dividing both sides by 3
x² = 9/3
x² = 3
x = √3
x = +3 and -3
b) (x-3)² = 1
Taking square root of both sides to remove the square,
√(x-3)² = √1
x-3 = √1
x-3 = 1 and x-3 = -1 (note that √1 is +1 and -1)
x = 4 and x = 2
c) 4(x-3)² = 1
Dividing both sides by 4 we have;
(x-3)² = 1/4
Taking the square root of both sides to eliminate the square.
√(x-3)² = √1/4
x-3 = √1/4
x-3 = +1/2 and x-3 = -1/2
x = 1/2+3 and x = -1/2+3
x = 3.5 and 2.5
d) 2(x-3)² = 12
Dividing both sides by 2 we have;
(x-3)² = 12/2
Taking the square root of both sides to eliminate the square.
√(x-3)² = √12/2
x-3 = √6
x-3 = 2.5 and x-3 = -2.5
x = 2.5+3 and x = -2.5+3
x = 5.5 and 0.5
e) The answers to questions 1 to 4 has different solutions due to the different value of the coefficient of (x-3)² and also the value at the right hand side of the equations also differs, hence, the reason for the difference in their answers.
<u>Answer:</u>
X and Y are stochastically dependent RVs .
<u>Step-by-step explanation:</u>
Let ,
X = sum of the values that come up after throwing n (≥ 1) fare dice.
Y = number of times an odd number come up.
Let, n = 3
then, P(X =6) = p (say) clearly 0 < p < 1
and P (Y = 3) = 
And,
P( X = 6, Y = 3) = 0 ≠ 
Hence, X and Y are stochastically dependent RVs
Answer:
She spent 2 and a half hours doing extra work.
