Answer:
The 84th term of the arithmetic sequence -5,15,35, ... is 1675.
Step-by-step explanation:
The arithmetic sequence -5,15,35, ... increases by 20 per term. Add 20 to the prior term to find the new term. Do this 83 times from -5, and you reach 1675.
The answer to your question is
x^33
diagonal = sqrt(a^2 +b^2)
20 = sqrt(12^2 +b^2)
20= sqrt(144+b^2)
20^2 = 144 + b^2
400 = 144 + b^2
256 = b^2
b = sqrt(256) = 16
it is 16 inches wide