Use substitution to solve each system of equations. Please explain how to solve these types of problems!!! Tysm y = x + 5
3x + y = 25

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

The magnitude, m, of an earthquake is defined to be m=log l/s, where i is the intensity of the earthquake (measured by the amplitude of the seismograph wave) and s is the intensity of a “standard” earthquake, which is barely detectable. what is the magnitude of an earthquake that is 1,000 times more intense than a standard earthquake? use a calculator. round your answer to the nearest tenth.

The interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a