Answer:
a) (+) × (?) = (+)
(?) = (+)
b) (-) × (+) = ?
? = (-)
c) (?) × (-) = ?
? is undefined
Step-by-step explanation:
a) (+) × (?) = (+)
From the given equation in the question, by dividing both side of the equation by (+), we have;
((+) × (?))/(+) = (+)/(+)
(?) = (+)/(+) = (+)
Therefore, we have;
(+) × (+) = (+)
(?) = (+)
b) (-) × (+) = ?
From the given equation in the question we apply the operation rules as follows;
(-) × (-) = (+)
(-) × (+) = (-)
Therefore;
(-) × (+) = ? = (-)
? = (-)
c) (?) × (-) = ?
From the rules of multiplication, we have;
(-) × (-) = (+)
(+) × (-) = (-)
Therefore, when (?) = (-), ? = +, from which we have;
(?) ≠ ?, which is an error
Similarly, when (?) = (+), ? = -, therefore, (?) and ?, always changes sign
Therefore, the equation, (?) × (-) = ?, is undefined.
Answer:
The correct option is;
e. 2500
Step-by-step explanation:
The formula for sample size is given by the following formula;

At 95%, z = 1.96
ε = Margin of error = 0.02 = 2%
Finding the sample size, n, given only the margin of error is by the following formula;
Margin of error = 100/√n
Therefore, we have;
2 = 100/√n
√n = 100/2 = 50
n = 50² = 2500
Therefore, the correct option is e. 2500.
We can write this as the difference of squares:
(5b⁸+8c)(5b⁸-8c)
To write as the difference of squares, take the square root of each term first:
√25b¹⁶ = 5b⁸; √64c² = 8c
Now we write this as a sum in one binomial and a difference in the other:
(5b⁸+8c)(5b⁸-8c)
Your answer would be 5 1/4