The table below gives the value of the linear function f for several values of x. What is the value of a + b?
X 2 3 4
F(x) a 8 b

Question

Quizplus · Accepted Answer

The value of a + b is none of the listed answers. The value of a + b is 16.
Solution
Use the linear function equation.
f(x) = mx + b
1. When x = 3, 3m+b = 8. "Guess and check" values for m and b
When m = 2, b = 2
2. Find the missing outputs in the table
f(2) = 2(2) + 2 = 6
f(4) = 4(2) + 2 = 10
3. Add a + b
6 + 10 = 16

The Table Below Gives the Value of the Linear Function