If y varies directly with x, means that they can be modeled by a linear equation, lets choose a line with 0 y intercept, that is:
y = mx + b
y = mx
where m is the slope of the line, now we plug in the data we have:
y = mx
20/3 = m(30)
solving for m:
m = (20/3)(1/30)
m = 20/90
m = 2/9
so the line equation, or function modeling the y and x relationship is:
y = (2/9)x
Answer and Step-by-step explanation:
Solve for b.
A = 
Divide by h and multiply by 2 from both sides.

Subtract a from both sides.

Answer:
a) B
b) draw a closed circle right before 0.1 (where 0.083 would be)
c) 1/12
Answer:
454
Step-by-step explanation:
The formula for this arithmetic sequence is: 9n+4
1st term: 9(1)+4 = 13
2nd term: 9(2)+4 = 22
3rd term: 9(3)+4 = 31
4th term: 9(4)+4 = 40
.
.
.
50th term: 9(50)+4 = 450+4
= 454