Answer:
84
Step-by-step explanation:
Pretend her first 3 quizzes were all 83 since that was the average. So the 4th was 87.
83+83+83+87 = 336
Divide by the total number of quizzes because they are equally weighted.
336/4 = 84
Her new average score is 84.
Answer:
x > -1
Step-by-step explanation:
-3x + 15 < 18
Subtract 15 from each side
-3x + 15-15 < 18-15
-3x < 3
Divide each side by -3, remembering to flip the inequality
-3x/-3 > 3/-3
x > -1
Answer:
(x + 3)² - 12
Step-by-step explanation:
x²+6x-3
= x²+ 6x + 9 - 12
= (x + 3)² - 12