Answer:

Step-by-step explanation:
there are a total of 20 marbles and the chance that it is blue is 8/20 so multy that by itself and the answer is 4/25
<h2>
Answer:</h2>
a. <-13/2,-13/2>
<h2>
Step-by-step explanation:</h2>
The projection of a vector u onto another vector v is given by;
=
----------------(i)
Where;
u.v is the dot product of vectors u and v
|v| is the magnitude of vector v
Given:
u = <-6, -7>
v = <1, 1>
These can be re-written in unit vector notation as;
u = -6i -7j
v = i + j
<em>Now;</em>
<em>Let's find the following</em>
(i) u . v
u . v = (-6i - 7j) . (i + j)
u . v = (-6i) (1i) + (-7j)(1j) [Remember that, i.i = j.j = 1]
u . v = -6 -7 = -13
(ii) |v|
|v| = 
|v| = 
<em>Substitute these values into equation (i) as follows;</em>
= ![[\frac{-13}{(\sqrt{2}) ^2}][i + j]](https://tex.z-dn.net/?f=%5B%5Cfrac%7B-13%7D%7B%28%5Csqrt%7B2%7D%29%20%5E2%7D%5D%5Bi%20%2B%20j%5D)
= ![\frac{-13}{2} [i + j]](https://tex.z-dn.net/?f=%5Cfrac%7B-13%7D%7B2%7D%20%5Bi%20%2B%20j%5D)
This can be re-written as;
= 
= 
Answer:
Step-by-step explanation:
Four
Start by trying to understand what f(x) means. First of all it is the same thing as y in the equation given in question 4. It is a shorthand that tells you that you put an x in wherever you see an x on the right.
More important, it tells you what to put in for x on the right.
f(z) would tell you to put z in for x anywhere there is an x on the right.
f(z)=2z+1. It is just a shorthand to tell you what to do on the right.
f(2) means put a 2 in for the x on the right. Read all of this carefully. You need to know it.
f(2) = 2(2) + 1
f(2) = 4 + 1
f(2) = 5
=================
Five
f(x) = -x - 5 The minus 4 is not going to change what you do.
f(-4) = -(-4) - 5 Wherever you see an x you put in a minus 4
f(-4) = 4 - 5
f(-4) = - 1
======================
Just so you know, consider a more complicated example
f(x) = 20x^3 + 7x^2 + 4x + 19
Where ever you see an x put in 2
f(2) = 20*(2^3) + 7*(2^2) + 4(2) + 19
f(2) = 20*8 + 7*4 + 4*2 + 19
f(2) = 160 + 28 + 8 + 19
f(2) = 215
Note x can be anything the question tells you it is.
f(5) means put a 5 in for every x.
1. The perimeter is 20. How I got that is to add all of them together- 9+3+3+3+2=20. The area is the area is 15. How I got that was I did the little square with 3 and 2 first. 3 times 2 = 6, then I did the 3 and 3 which = 9 and added those together 9+6=15
2. The perimeter is 15. How I got that is I add them all together. 6+3+2+2+2=15. The area is 10. I did 3 times 2 = 6, 2 times 2 = 4, 6+4=10