Counting numbers are to be formed using only the digits 1, 9, 8, 6, 2, 4, and 5. determine the number of different possibilities for two-digit numbers

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.