7) Certainly there is a typo in the statement, just see that the expression of item (ii) is different from that of item (i). Probably the correct expression is:

. With this consideration, we can continue.
(i) Let E the expression that we are analyzing:

Since (x-1)² is a perfect square, it is a positive number. So, E is a result of a sum of two positive numbers, 2(x-1)² and 3. Hence, E is a positive number, too.
(ii) Manipulating the expression:

So, it's the case when E=0. However, E is always a positive number. Then, there is no real number x that satisfies the expression.
8) Let E the expression that we want to calculate:

Multiplying by (2-1) in the both sides:

Repeating the process, we obtain:
Answer:
D
Step-by-step explanation:
Answer:
x=-5 & y=-2
Step-by-step explanation:
y= 3x+13
y= x-3
x-3=3x+13
-3=2x+13
-10=2x
x=-5
then
y=3(-5)+13
y=-15+13
y=-2
Answer: 14
Step-by-step explanation:
- Degrees of freedom is the number of values in the evaluation of a test statistic that are free to vary.
For t-statistic , the degree of freedom for a sample with sample size 'n' is given by :-

Given : Sample size : n-1
Then, the number of degrees of freedom the t-value will have :-

Hence, the t-value will have 14 degrees of freedom.
Answer:
x = -9
Step-by-step explanation:
4x+10=-26
Subtract 10 from each side
4x+10-10=-26-10
4x = -36
Divide each side by 4
4x/4 = -36/4
x = -9