Solve the system of linear equations using Gaussian or Gauss-Jordan elimination (row echelon form, then substitute). Check your answer in your calculator when finished.
1) x + 4y = 20
2x + 5y + 4z = 20
2x - 2y + 3z = -6

Which property is illustrated by the following statement? if hxa rgi, then rgi hxa.

The local farm is advertising a special on fresh picked peaches. the farm charges $4.25 to pick your own peck of peaches and $3.50 for each additional peck you pick. write an equation for the total cost of peaches in terms of the number of pecks. deine your variables. how much does it cost to pick 3 pecks of peaches?

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?