Answer:
see explanation
Step-by-step explanation:
Given
f(x) = ax + b
x = 2 → f(x) = 1 and x = - 1 → f(x) = - 5 ( from the table )
Substitute these values into f(x) = ax + b, that is
2a + b = 1 → (1)
- a + b = - 5 → (2)
Subtract (2) from (1) term by term to eliminate b
3a = 6 ( divide both sides by 3 )
a = 2
Substitute a = 2 into (2) and evaluate for b
- 2 + b = - 5 ( add 2 to both sides )
b = - 3
(b)
When x maps onto itself then
ax + b = x, that is
2x - 3 = x ( subtract x from both sides )
x - 3 = 0 ( add 3 to both sides )
x = 3
Thus a = 2, b = - 3 and x = 3
