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1. Find the value of 5/ (square rooted) X /20.

/5 + /20 = k/5, where k is an integer.

Find value of k.

Find value of /5 + /45 divided by /20.

(Non calculator)
2. (Original post by Eddie87-04)
Find the value of 5/ (square rooted) X /20.

/5 + /20 = k/5, where k is an integer.

Find value of k.

Find value of /5 + /45 divided by /20.

(Non calculator)
First question is too ambiguous. Do you mean: (5/√x)/20, or 5/(√x/20) ?

The second one, there are no numerators on the left hand side...
Same with the third.

If I took them to mean (1/5 + 1/45)/20, then:

(9/45 + 1/45)/20
(10/45)/20
(10/45)*(1/20)
10/900
1/90
3. Thanks. I mean the square root of 5 X the square root of 20.

square root of 5 + square root of 20 = k/5, where k is the integer.

Then it says find value of k.

Then find the value of sqaure root of 5 + square root of 45 divided by square root of 20.

How do you do this with out a calculat
4. (Original post by Eddie87-04)
Find the value of 5/ (square rooted) X /20.

/5 + /20 = k/5, where k is an integer.

Find value of k.

Find value of /5 + /45 divided by /20.

(Non calculator)
Nor sure what the first one means, but the others, ...

√5 + √20 = k/5
5 + 2√(5*20) + 20 = k²/5²
2*10 + 25 = k²/25
25*45 = k²
k = 5*3√5
k = 15√5
======

(√5 + √45)/√(20)
√5/√(20 + √(45)/√(20)
√(1/4) + √(225/100)
1/2 + 15/10 = 5/10 + 15/10 = 20/10 = 2
==========================
5. (Original post by Eddie87-04)
Thanks. I mean the square root of 5 X the square root of 20.

...

How do you do this with out a calculat
√5 * √20
= √(5*20)
= √(100)
= 10
===
6. (Original post by Eddie87-04)
Thanks. I mean the square root of 5 X the square root of 20.

square root of 5 + square root of 20 = k/5, where k is the integer.

Then it says find value of k.

Then find the value of sqaure root of 5 + square root of 45 divided by square root of 20.
sqrt(5) * sqrt(20) = sqrt(100) = 10

sqrt(5) + sqrt(20) = sqrt(5) + sqrt(4*5) = sqrt(5) + 2sqrt(5) = 3sqrt(5)
Hence, k = 3

(sqrt(5) + sqrt(45))/sqrt(20) = (sqrt(5) + 3sqrt(5))/2sqrt(5) = 4sqrt(5)/2sqrt(5) = 2

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