Solve the equation 21x + 27 = 300 using systematic trials. Explain each step.

21x + 27 = 300

21x = 300 - 27 = 273

x = 300/21 = 14.3

21x + 27 = 300

21*10 + 27 = 237 -- too small
21*20 + 27 = 447 -- too big
21*15 + 27 = 342 - too big
21*14 + 27 = 321 -- too small
21*13 + 27 = 300

To solve the equation 21x + 27 = 300 using systematic trials, we will start by isolating the variable x.

Step 1: Subtract 27 from both sides of the equation:
21x + 27 - 27 = 300 - 27
21x = 273

Step 2: Divide both sides of the equation by 21 to solve for x:
21x/21 = 273/21
x = 13

So, the solution to the equation 21x + 27 = 300 using systematic trials is x = 13.