Use substitution to solve the system of equations -2x+y= -1 and 6x-2y = 12. show your work.​

Two angles are complementary. the large angle is 36 more than the smaller angle. what is the measure of the large angle?

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

Which geometric principle is used to justify the construction below?