Answer:
syd is 23 and dev is 69
Step-by-step explanation:
Let Dev's age be x and Syd's age be y
Since Dev is 3 times older than Syd, we may write
x
=
3
y
Since the sum of their ages is 92, we may write
x
+
y
=
92
Now replacing x with 3y, we get :
3
y
+
y
=
92
Hence
y
=
92
4
=
23
and so Syd is 23 year old.
Back substituting we get Dev is 69 years old.
For this case we have the following functions:

We must find
when
.
So:

We apply distributive property to the terms within parentheses taking into account that:

We add similar terms taking into account that different signs are subtracted and the sign of the major is placed:

Thus, we have to:

Then, with x = 2:

Equal signs are added and the same sign is placed.
Answer:

Answer:
5
Step-by-step explanation:
The slope is 5 because the equation is y = 200-5x where 5 is the slope because it is the rate of change.