Let x = length and y = width
Then, 2x + 2y = 70 and xy = 49.
Since 2x + 2y = 70, y = 35 - x
y = 35 - x
x is the independent variable
domain: 0 < x < 35
range: 0 < y < 35
x(35 - x) = 49
x2 - 35x + 49 = 0
x = [35 ± √1029] / 2 = 33.539 or 1.461
The dimensions of the tomato patch would be 33.539 ft by 1.461 ft for a 70 square foot patch (There is enough fencing for maybe 1 row of tomato plants)