Question

A necklace and earrings cost $144. Six necklaces and five pairs of earrings cost $825

Answer 1

Explanation:

let necklace : x

let earrings : y

x+y=144 -1st eqn

6x+5y=825 -2nd eqn

y=144-X -3rd eqn

substitute eqn into 2nd eqn

6x+5(144-x)= 825

6x +720-5X =825 (expanded)

X = 825-720

X =105

substitute "X=105" into 1st eqn

(105)+y=144

y= 144-105

y=39

1 necklace = 105$

1 pair of earrings = 39$

(to check back: substitute the value into the original eqn)