### Home > PC > Chapter 2 > Lesson 2.3.3 > Problem 2-100

2-100.

Find a rule for a linear function

*g*such that*g*(1) = 3.5 and*g*(4) = 5. Homework Help ✎Use the result from above to express 3.5 + 4 + 4.5 + 5 in sigma notation.

Find the sum in part (a).

Find the slope of the line going through *g*(1) and *g*(4).

Substitute the point and the slope in the point-slope form to find the equation.

(*g*(*x*) − 5) = 0.5(*x* − 4)*g*(*x*) = 0.5*x* − 2 + 5*g*(*x*) = 0.5*x* + 3

Write the Sigma notation.

Add up the terms.