Answer:
21) 12 cm
22) 5.9 cm
Step-by-step explanation:
21) The base is 10, and if the other two sides are congruent and the perimeter is 36, we can figure out with simple algebra that the sides are 13 cm long.
Half of 10 is 5, so we can use the pythagorean theorem.
5^2+x^2=13^2
Rearranging the variables we have 169-25=x^2
144=x^2
x can be plus or minus 12, but since negative length is impossible we find that x is positive 12 cm.
22) We want to use sine, because we have opposite and hypotenuse. A simple and easy way to memorize this is the SohCahToa method. If we have opposite (O) and hypotenuse (H) we have OH. Soh has the letters O and H, and the S means we should use sine.
sine 36=a/10
Plug this into a calculator or desmos scientific calculator to get a=5.9
Answer:
14/45
Step-by-step explanation:
So we have the fraction:
We can do this algebraically. Follow to following steps:
Let's let this number equal to n. Thus:
Since there is only 1 digit repeating, let's multiply everything by 10. So:
Now, subtract n from both sides:
On the left, substitute the number for n. On the right, combine like terms:
All of the 1s will cancel. So:
Subtract:
Divide both sides by 9:
Remove the decimal by multiplying both sides by 10:
Reduce:
And we're done!
Use a calculator to check:
Answer:
10√5 - 5√2
or
5(2√5 - √2)
Step-by-step explanation:
Given:
2√5(5 - 5√5)
Required:
Multiply and simplify
Solution:
2√5(5 - 5√5)
Apply distributive property by multiplying each term in the bracket by 2√5
2√5*5 - 2√5*5√5
2*5√5 - 2*5√5*√5
10√5 - 10√25
10√5 - 10*5
10√5 - 50
10√5 - (25*2)
10√5 - 5√2
Or
5(2√5 - √2)
Answer:
7/6
Step-by-step explanation:
7/3÷4/5
7/3×5/4
35/12
Now the multiplication
2/5×35/12
70/60
7/6
Assuming that each marble can be picked with equal probability, we notice that there is a total of
marbles, of which 2 are red.
So, the probability of picking a red marble is
In fact, as in any other case of (finite) equidistribution, we used the formula
