Pair of Linear Equations in Two Variables

The father's age is six times his son's age. Four years hence, the age of the father will be four times his son's age. The present ages, in years, of the son and the father are, respectively

A two digit number is k times the sum of its digits. The number formed by interchanging the digits is the sum of digits multiplied by

y = a + b/x where a, b are real numbers, if y = 1 when
x = - 1 and y = 5 when x = - 5, then a + b equals

The pair of equations y = 0 and y = - 7 has

The paii- of equations x = a and y = b graphically represents lines which are

A pair of linear equations which has a unique solution x = 2, y = - 3 is