Respuesta :
15% discount means u r paying 85% for it
x = original price
0.85x + 12 < x
12 < x - 0.85x
12 < 0.15x
12/0.15 < x
80 < x.....so for it to be cheaper online, it would have to cost more then 80....so 81 or higher
x = original price
0.85x + 12 < x
12 < x - 0.85x
12 < 0.15x
12/0.15 < x
80 < x.....so for it to be cheaper online, it would have to cost more then 80....so 81 or higher
Let
x------> the regular price of the stereo in dollars
we know that
If Jay buy a stereo online
He has to pay
[tex]x(1-0.15)+\$12=0.85x+\$12[/tex]
If Jay buy a stereo at the local store
He has to pay
[tex]x[/tex]
Is cheaper for Jay to buy the stereo online when
[tex]0.85x+\$12 < x\\0 .85x-x < -12\\- 0.15x < -12\\ 0.15x > 12\\ x > 12/0.15\\ x > \$80[/tex]
therefore
the answer is
The regular price must be greater than [tex]\$80[/tex] for Jay to buy the stereo on line