Answer: 20
Step-by-step explanation: see screenshot
Step-by-step explanation:
2x - 10y > -20
=> x - 5y > -10
or x - 5y +10 > 0
60% of 20 quizzes = 60/100*20 quizzes = 12 quizzes
Amount of quizzes remaining = 50 quizzes - 20 quizzes = 30 quizzes
He passes 80% of those 30 quizzes, so
80/100 * 30 quizzes = 24 quizzes
So, he passed 12 quizzes from the initial bunch and 24 quizzes from the rest, which totals to 12 quizzes + 24 quizzes = 36 quizzes.
Then, you see that he passed 36 quizzes, out of the total 50 quizzes, so the ratio is 36 quizzes / 50 quizzes = 36/50, which when converted as a percentage is 36/50 * 100% = 72%.
Therefore, he passed 72% of the quizzes for the entire year.
Slope: 4
Y-intercept = 1/2
-3. Put the two equation equal to each other and solve.
4x+18=2x+12
-2x=-2x
2x+18=12
-18=-18
2x=-6
2x/2=-6/2
x=-3
