For questions 3-4, determine the number of solutions to the system of nonlinear equations. (Can someone please help me please)

Which math sentence can be used to determine if the triangle is a right triangle?

Which equation can be solved to find one of the missing side lengths in the triangle? cos(60o) = cos(60o) = cos(60o) = cos(60o) = mark this and return

On a certain portion of an experiment, a statistical test result yielded a p-value of 0.21. what can you conclude? 2(0.21) = 0.42 < 0.5; the test is not statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 21% of the time, so the test is not statistically significant. 0.21 > 0.05; the test is statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 79% of the time, so the test is not statistically significant. p = 1 - 0.21 = 0.79 > 0.05; the test is statistically significant.