Given the inequality:
10x + 12y ≤ -20
to check if a point is a solution, you have to replace the point and check if the inequality is satisfied.
A Replacing (12, -6) into the inequality, we get:
10(12) + 12(-6) ≤ -20
120 - 72 ≤ -20
48 ≤ -20
48 is greater than -20, then (12, -6) doesn't satisfy the inequality
B Replacing (-9, 6) into the inequality, we get:
10(-9) + 12(6) ≤ -20
-18 ≤ -20
-18 is greater than -20, then (-9, 6) doesn't satisfy the inequality
C Replacing (9, -4) into the inequality, we get:
10(9) + 12(-4) ≤ -20
42 ≤ -20
42 is greater than -20, then (9, -4) doesn't satisfy the inequality
D Replacing (-12, 8) into the inequality, we get:
10(-12) + 12(8) ≤ -20
-24 ≤ -20
then (-12, 8) satisfies the inequality
