A boy has 5-dollar coins and a 10-dollar coins. They are eight coins all together and their value is 55 dollars. How many of each kind does he have?

Guest Mar 16, 2021

#1**+1 **

let's define some variables: x and y, for the 5-dollar coins and the 10-dollar coins, respectively.

now let's create a system of equations -

x + y = 8

5x + 10y = 55.

we can simplify that second equation by dividing both sides by 5. now we get:

x + y = 8

x + 2y = 11

let's use elimination and subtract these two equations.

subtracting, we get y = 3.

now to solve for the amount of 5-dollar coins there are, we can plug in our value of y in one of the equations.

x + 3 = 8

x = 8 - 3

x = 5.

hope this helped! please let me know if you are confused about anything i did :)

euph0ria Mar 16, 2021