The cost of one kent is $ 5
The cost of one dubbles is $ 2
Solution:
Let "x" be the cost of one kent
Let "y" be the cost of one dubbles
Elentine bought 2 kents and 6 dubbles for a total cost of $22
Therefore,
2x + 6y = 22
Reduce,
x + 3y = 11
x = 11 - 3y ------- eqn 1
Boondin bought 9 kents and 4 dubbles for a total cost of $53
9x + 4y = 53 ---------- eqn 2
Substitute eqn 1 in eqn 2
9(11 - 3y) + 4y = 53
99 - 27y + 4y = 53
23y = 46
Divide both sides by 23
y = 2
Substitute y = 2 in eqn 1
x = 11 - 3(2)
x = 11 - 6
x = 5
Thus the solution is (5, 2)