Answer with Step-by-step explanation:
We are given that

For each real number 
To prove that f is one -to-one.
Proof:Let
and
be any nonzero real numbers such that

By using the definition of f to rewrite the left hand side of this equation

Then, by using the definition of f to rewrite the right hand side of this equation of 

Equating the expression then we get




Therefore, f is one-to-one.
15 - x = 2(x + 3)
15 - x = 2x + 6
15 = 3x + 6
9 = 3x
3 = x
x = 3
Answers:
x = 4
EF = 14
CF = 7
EC = 7
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Work Shown:
C is the midpoint of segment EF. This means that EC = CF. In other words, the two pieces are congruent.
Use substitution and solve for x
EC = CF
5x-13 = 3x-5
5x-13+13 = 3x-5+13
5x = 3x+8
5x-3x = 3x+8-3x
2x = 8
2x/2 = 8/2
x = 4
Now that we know that x = 4, we can use this to find EC and CF
Let's compute EC
EC = 5x - 13
EC = 5*x - 13
EC = 5*4 - 13 ... replace x with 4
EC = 20 - 13
EC = 7
Let's compute CF
CF = 3x - 5
CF = 3*x - 5
CF = 3*4 - 5 ... replace x with 4
CF = 12 - 5
CF = 7
As expected, EC = CF (both are 7 units long).
By the segment addition postulate, we can say EC+CF = EF
EC+CF = EF
EF = EC+CF
EF = 7+7
EF = 14
Answer:
The Y-intercept or number after the + or - sign is what you start with then you use rise/run rise=the y value and run = x value to use the constant
Step-by-step explanation: