True. Two lines intersect in a single point.
This in what I got:
(-7i)(10i)
-70i
Sum = n/2[2a + (n - 1)d] where a = first term, n = number of terms and d = common difference
(a) 30/2(2 x 5 + (30 - 1) x d) = 1455
10 + 29d = 1455 / 15
29d = 97 - 10
d = 87 / 29 = 3
(b) 7/2(2 x 9 + (7 - 1)d) = 0
18 + 6d = 0
6d = -18
d = -3
Based on the line of best fit, the length of this catfish can be predicted to be 38 inches.
<u>Given the following data:</u>
- Weight of catfish, x = 40 pounds.
<h3>What is a line of best fit?</h3>
A line of best fit is also referred to as a trend line and it can be defined as a statistical (analytical) tool that is used in conjunction with a scatter plot, in order to determine whether or not there's any correlation between a data.
From the graph of the data, we have the following linear equation:

Substituting the value of x, we have:

y = 38 inches.
Read more on scatterplot here: brainly.com/question/6592115
Sum/difference:
Let

This means that

Now, assume that
is rational. The sum/difference of two rational numbers is still rational (so 5-x is rational), and the division by 3 doesn't change this. So, you have that the square root of 8 equals a rational number, which is false. The mistake must have been supposing that
was rational, which proves that the sum/difference of the two given terms was irrational
Multiplication/division:
The logic is actually the same: if we multiply the two terms we get

if again we assume x to be rational, we have

But if x is rational, so is -x/15, and again we come to a contradiction: we have the square root of 8 on one side, which is irrational, and -x/15 on the other, which is rational. So, again, x must have been irrational. You can prove the same claim for the division in a totally similar fashion.