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What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

Afurniture manufacturer produces chairs and sofas. each chair requires 10 yards of fabric, and each sofa requires 20 yards of fabric. the manufacturer has 300 yards of fabric available. to fulfill orders, the number of sofas must be at least twice the number of chairs. let x be the number of chairs and y the number of sofas. which inequalities are described in the problem? check all of the boxes that apply

How many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.