Let x be the number of 5 points question.
Let y be the number of 2 points question.
Total number of questions is 38
x + y = 38
Total points is 100
5x + 2y = 100
x + y = 38 ------------- (1)
5x + 2y = 100 ---------(2)
From (1):
x + y = 38
x = 38 - y -------------- sub into (2)
5(38 - y) + 2y = 100
190 - 5y + 2y = 100
3y = 90
y = 30 ------------------ sub into (1)
x + 30 = 38
x = 38 - 30
x = 8
There are 8 5-point questions and 30 2-point questions
Answer:
D
Step-by-step explanation:
X2+y2–x–2y–11/4=x2−x+14−14+y2−2y+4−4−11/4=(x−12)2+(y−2)2−14−4−114=(x−12)2+(y−2)2−7=0(x−12)2+(y−2)2=(7√)2
Center(1/2 ,2)
radius = \sqrt 7
Answer:
x - 13 = 13 - x
Step-by-step explanation:
The commutative property of addition is a+b=b+a
The third equation is the only one not following the rule. It states that a-b=b-a, whoich is not true.
For exaple, 2-1 is not equal to 1-2.
