When drawn in standard position, an angle B has a terminal ray that lies in the second quadrant and sin(B)=5/13. Find the value of cos(B), (show your answer as a fraction). Please show all your work

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What number should be added to both sides of the equation to complete this square? x^2-10x=7

Phyllis and chen are saving money to go to a football game. each friend starts with some money and saves a specific amount each week. phyllis made a graph to show the total she has saved at the end of each week. chen wrote an equation to show the total, y, he has saved at the end of each week, x. y = 15x + 15 compare the amount that each friend has when both friends start saving. select the correct answer from the drop-down menu to complete the statement. phyllis starts with $ and chen starts with $

Y+ 2/y is it a polynomial in one variable or not? and if so, why?