multiply all terms in the second equation by 2 to get the coefficient on the y variable to be -6.

65 % ------------------ 23.4 items
100 % ----------------- x items
65 : 100 = 23.4 : x
65 x = 100 * 23.4
65 x = 2340
x = 2340 : 65
x = 36
Answer: there were 36 items on the test.
The sequence is an geometric progression;
Nth=a₁r^(n-1)
a₁ is the first term=-1
r=ratio=a₂/a₁=6/-1=-6
Nth=-1(-6^(n-1)
NTh=an
a₁=-1(-6⁰)=-1
a₂=-1(-6¹)=6
a₃=-1(-6²)=-36
a₄=-1(-6³)=216
therefore this serie is rising at an increasing fast speed, it is an geometric progression.
The answer is 
Steps: (<em>in the attachment</em>)↓↓↓↓↓
<em>Hope this helps!!</em>
Answer:
It looks like the third one, C
Step-by-step explanation:
Every time c increases by 1, d increases by 2
That means the slope will be 1/2
That means the slope is positive
Which means that there can only be one answer, C