which system of equations models this problem?

the variable x represents the number of long sleeve shirts nancy bought and the variable y represents the number of short sleeve shirts she bought?

nancy bought 531 shirts for her business. she bought 2 times as many short sleeve shirts as long sleeve shirts. how many of each type of shirt did she buy?

a. x + y = 531
y = 2x

b. x - y = 531
y = 2x

c. x + 2y = 531
y = 2x

d. x + y = 2
y = 531x

Which triangle congruence postulate or theorem justifies my claim that the steps i made using construction paper and scissors produce an isosceles triangle? was it sss, sas, asa, aas, or hl?

Atest of sobriety involves measuring the subject's motor skills. a sample of 31 randomly selected sober subjects take the test and produce a mean score of 64.4 with a standard deviation of 2. a claim is made that the true mean score for all sober subjects is equal to 65. for each part below, enter only a numeric value in the answer box. for example, do not type "z =" or "t =" before your answers. round each of your answers to 3 places after the decimal point. (a) calculate the value of the test statistic used in this test. test statistic's value = (b) use your calculator to find the p-value of this test. p-value = (c) use your calculator to find the critical value(s) used to test this claim at the 0.2 significance level. if there are two critical values, then list them both with a comma between them. critical value(s) =

Sections of prefabricated wood are each 5 1/3 feet long. how long are 7 1/2 sections placed end to end?