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.
What are the measurements?
Step-by-step explanation:
-2 (4a + 4b) + 5a > -35
-8a -8b + 5a > -35
-3a -8b > -35
for a
-3a > -35 + 8b
a < -35 + 8b ÷ -3
a < 35 - 8b ÷ 3
for b
-3a - 8b > -35
-8b > -35 + 3a
b < -35 + 3a ÷ -8
b < 35 - 3a ÷ 8
Answer: 35/3 or 11.6
Step-by-step explanation:
3x-7=28
Add 7 to each side
3x=35
Divide by 3
I am not sure is you are supposed to solve or rewrite but for solving its this picture, tell me if its rewriting the problem and ill give you that as well!