Answer:
3/7
Step-by-step explanation:
The first black marble is 10/15 and the second is 9/14. Multiply them together to get 3/7 after you simplify it.
Answer:
The tree is 28 feet tall.
Step-by-step explanation:
It is given that:
Height of flag pole = 8 feet
Shadow of flag pole = 6 feet
Ratio of height to shadow = 8 : 6
Shadow of nearby tree = 21 feet
Height of nearby tree = x
Ratio of height to shadow = x : 21
8 : 6 :: x : 21
Product of means = Product of extremes
6x = 8*21
6x = 168
Dividing both sides by 6
Therefore,
The tree is 28 feet tall.
Work inside the brackets first, and then you can multiply the two equations if they are able to be mutiplied...
Answer:
(r^2 - r - 1)(r^2 + r - 1).
Step-by-step explanation:
r^4 - 3r^2 + 1
We need to make this into a perfect square so the r^4 and the 1 fit the bill but not the -3r^2 so we have to correct for that.
A perfect square would be:
r^4 - 2r^2 + 1 ( = (r^2 - 1)^2 )
But we need -3r^2 so we add - r^2 at the end:
= (r^4 - 2r^2 + 1) - r^2 So now we have the difference of 2 squares and we write:
(r^2 - 1)^2 - r^2
= (r^2 - 1 - r)(r^2 - 1 + r)
= (r^2 - r - 1)(r^2 + r - 1)
