Answer:
-4x-13
Step-by-step explanation:
To figure out the sum, you have to add like terms.
This is how it would look like:

He gave away 9 (20 x (3/7) =9) so 21-9=12
Answer:
A(2,2)
Step-by-step explanation:
Let the vertex A has coordinates 
Vectors AB and AB' are perpendicular, then

Vectors AC and AC' are perpendicular, then

Now, solve the system of two equations:

Subtract these two equations:

Substitute it into the first equation:

Then

Rotation by 90° counterclockwise about A(2,2) gives image points B' and C' (see attached diagram)
This is what I put in my response
For me I thought that algebra was better. I loved algebra I mean math is math somethings in math are hard, somethings are easy, sometimes in math you will come across something that seems impossible. Sometimes you will fly thru but, what makes the journey bearable is the people around you. Why I think algebra is better is because of the people that were in math course with me and my teacher because. The teachers make all the difference.
Answer:
The answer to your question is below
Step-by-step explanation:
14) sin Ф = 32/33
sin Ф = 0.9697
Ф = 75.86°
15) sin Ф = 16/36
sin Ф = 0.444
Ф = 26.39°
16) sin Ф = 29/36
sin Ф = 0.806
Ф = 53.66°
17) cos Ф = 11/34
cos Ф = 0.324
Ф = 71.12°
18) sin Ф = 21/40
sin Ф = 0.525
Ф = 31.67°
19) cos Ф = 6/14
cos Ф = 0.429
Ф = 64.62°
20) cos Ф = 38/39
cos Ф = 0.974
Ф = 13°