Question

f(x) is a linear function. If f(1)= -1 and f(2)= 14, find the value of f(15).

Answer 1

Answer:

209

Step-by-step explanation:

let linear equation be ax+b.

atq,

f(1)=-1

so, a*1+b=-1

=a+b=-1.... (1)

similarly,

f(2)=14

so, a*2+b=14

=2a+b=14...... (2)

Now, subtract 2 equation from 1 equation,

a + b =-1

2a + b =14

so, after subtracting, we get:

a =15. put this value of a in 1 equation,

so, 15+b=-1

b=-1-15

b=-16.

Now, f(15)= a*15+b

=15*15+(-16)

=225-16

=209

Answer 2

Step-by-step explanation:

209 is the correct answer