The sum of the first n terms of an arithmetic sequence is n/2(4n + 20). a) Write down the expression for the sum of the first (n − 1) terms.
b) Find the first term and common difference of the above sequence.
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Name each raycalculation tip: in ray "ab", a is the endpoint of the ray.

If you are trying to move an attached term across the equal sign (=), what operation would you use to move it?

The volume of gas a balloon can hold varies directly as the cube of its radius. imagine a balloon with a radius of 3 inches can hold 81 cubic inches of gas. how many cubic inches of gas must be released to reduce the radius down to 2 inches?