Answer:
a = 19
Step-by-step explanation
First, note that the rate of change of a linear function is known as its slope.
Given the coordinates (x1, y1) and (x2, y2), the formula for calculating the slope is expressed as;
Using the coordinates (10, 27) and (11, a) where m = -8, substitute the values into the formula;
Add 27 to both sides as shown;
Hence the value of a is 19