so you have your two equations 3x+7=5x-23 and solve for x which is your "number" leaving the answer to be <u>x=15</u>
Given that the score of the student on the quiz was 25c - 10(15 - c)
It can be seen that the first term of expression for her score (i.e. 25c) shows that 25 marks were awarded to each correct answer.
The second term of the expression (i.e. 10(15 - c)) represent that 10 marks were deducted from each wrong answer.
Thus, the number of wrong answers is 15 - c.
The sum of the correct answers and the wrong answers gives the total number of questions in the quiz.
Thus, the total number of questions in the quiz is given by 15 - c + c = 15.
Therefore, there are 15 questions in the quiz.
You are given the X value, replace x with 2 in the first equation to solve for y:
y=2x +3
y = 2(2) +3
y = 4+3
y = 7
Now replace y with 7 and x iwth 2 in the second equation and solve for k:
y = -x +k
7 = -2 +k
Add 2 to both sides:
9 = k
so k = 9
The point is given as k-2, which is 9-2 = 7, which is what y equals in the first equation.
K = 9
2/7 ≈ 0.2857
To determine percentage, move decimal 2 places to the right. ≈ 28.57%
