Solve the system please! -4x + 9y = 9 and x-3y=-6

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212

If you prove that ∆wxz is congruent to ∆yzx, which general statement best describes what you have proved?