Answer:
Mark is 18; his mother is 42.
Step-by-step explanation:
In 6 years, 12 years will be added to the total of their ages, so it will be 72. Since this is the total of Mark's age and twice Mark's age, his age at that time will be 72/3 = 24. His mother will be 48 at that time.
Now, they are 6 years younger than that, so they are 18 and 42.
Answer:
-5 as the gradeint because y=mx+c in which m is the gradient
Step-by-step explanation:
So we convert money into numbers 5 pounds of flour is 480 OK. Then we multiply 5*16 we get 80 then 480/80=006. Then we convert money back to numbers and we get 0.006. Answer A is correct.
There is one clock that shows the right time so we do not have to worry about the one which is always correct.
Talking about the second clock that loses a minutes in every 24 hours (or in a day), so after 60 days (since it has lost 60 minutes because it is losing 1 minute everyday) it will show 11:00 a.m when it is exactly the noon.
So this way, in total it will take
days before it shows the correct noon.
Now, the third clock gains a minute every 24 hours (or in a day) , after 60 days (when it has gained 60 minutes or a complete hour) it will show 1:00 p.m when it is exactly the noon.
This way, it will take
days (since it has gained a minute everyday) when it shows the correct noon.
Therefore, it will take 1440 days before all the three clocks show the correct time again.
Answer:
The work is in the explanation.
Step-by-step explanation:
The sine addition identity is:
.
The sine difference identity is:
.
The cosine addition identity is:
.
The cosine difference identity is:
.
We need to find a way to put some or all of these together to get:
.
So I do notice on the right hand side the
and the
.
Let's start there then.
There is a plus sign in between them so let's add those together:

![=[\sin(a+b)]+[\sin(a-b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%2Bb%29%5D%2B%5B%5Csin%28a-b%29%5D)
![=[\sin(a)\cos(b)+\cos(a)\sin(b)]+[\sin(a)\cos(b)-\cos(a)\sin(b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%29%5Ccos%28b%29%2B%5Ccos%28a%29%5Csin%28b%29%5D%2B%5B%5Csin%28a%29%5Ccos%28b%29-%5Ccos%28a%29%5Csin%28b%29%5D)
There are two pairs of like terms. I will gather them together so you can see it more clearly:
![=[\sin(a)\cos(b)+\sin(a)\cos(b)]+[\cos(a)\sin(b)-\cos(a)\sin(b)]](https://tex.z-dn.net/?f=%3D%5B%5Csin%28a%29%5Ccos%28b%29%2B%5Csin%28a%29%5Ccos%28b%29%5D%2B%5B%5Ccos%28a%29%5Csin%28b%29-%5Ccos%28a%29%5Csin%28b%29%5D)


So this implies:

Divide both sides by 2:

By the symmetric property we can write:
