The length of a rectangle is 12 feet more than twice the width. The area of the rectangle is 320 square feet

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.

What are the solutions for the following system? -2x^2+y=-5 y=-3x^2+5

£100.80 divided by 14 equals 7.2 how would we put this as money