What is the difference?
x2 - 2x-15
x2 + 2x-35
x2 + 3x + 12
(x-3)(x-5)(x+7)
x(x+3-12)
(x+3)(x-5xx+7)
x² + 3x+12
(x+3)(x-5)(x+7)
x2 + 3x-12
(x+3)(x-5)(x+7)

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827

The sum of the first eight terms of an arithmetic progression is 9m + 14. the fifth term of the06 progression is 2m - 6, where m is a constant.given that the first term of the progression is 26,find the value of the common difference, d and thevalue of m.

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years