4t+2c=200
2t+7c=400
I will solve for c in terms of t first
4t+2c=200
2c=200-4t
c=100-2t
Then I will substitute this in for c in the second equation to make it single variable
2t+7c=400
2t+7(100-2t)=400
2t+700-14t=400
300t=12
t=25
Tables cost $25 each
Plug t back into one of the ORIGINAL equations to find the cost of chairs
4(25)+2c=200
100+2c=200
2c=100
c=50
Chairs cost $50 each
Hope this helps! :)
For the answer to the question above,
The slope of the line of the line is calculated through the equation,
m = (y2 - y1) / (x2 - x1)
Using the first two points in the given,
m = (-7 - 9) / (-12 - 8) = 4/5
The line parallel to this has also a slope of 4/5. Through the point-slope form, the equation of the second line is,
y - -15 = (4/5)(x - -5)
Simplifying gives the answer of,
y = (4/5)x -11
Eliminating the fraction,
5y = 4x - 55
I hope my answer helped you.
It's simple just divide the total Miles traveled by the total hours;
287 m ÷ 3.5 (it's 3.5 because 30 mins is half of an hour)

= 82 miles per hour
So your final answer would be
82 miles per hour :)
<span>20, 21, 22, 24, 25, 26, 27, 28, 30. hope that helped</span>
32,64,128
Hope i helped :)