Math hw question helppp!!!!!!

ok so you have $5 bills and $1 bills you have 14 bills and all of them add up to $30 how many 5 dollars do u have and how many 1$ bills do you have
thanks!

x = number of $1 bills
14 - x = number of $5 bills

1x + 5(14 - x) = 30 {value of bill times number of bills equals total vlaue}
x + 70 - 5x = 30 {used distributive property}
-4x + 70 = 30 {combined like terms}
-4x = -40 {subtracted 70 from both sides}
x = 10 {divided both sides by -4}
14 - x = 4 {substituted 10, in for x, into 14 - x}

ten $1 bills
and
four $5 bills

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