Which system of equations below has exactly one solution?
a.) y = –8x – 6 and y = –8x + 6
b.) y = –8x – 6 and One-halfy = –4x – 3
c.)y = –8x – 6 and y = 8x – 6
d.) y = –8x – 6 and –y = 8x + 6
HEL I DONT GET THIS PLEAS :(

Ftara spends $219 a month for her car payment and she makes $3,200 a month, what percent of her monthly income is spent on her car payment?

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.

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