Answer:
5.7 is the answer I had the same question in my test
formula= LCM ×GCD of the numbers ÷ The first number
The solution would be like
this for this specific problem:
Given: 40
km/h
2 km
t = d / v
t = 2 km / 40 km/h
t = 0.05 h * 60 minutes = 3 minutes
<span>At
this rate, it would take 3 minutes for the red kangaroo to jump 2 km.</span>
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.
Answer:
The correct answer is B.) (4x - 7 + 5x + 5) and (9x + 12).
