J= -458! hope it helps :)
Perpendicular has slope that multiplies to -1 in other sloope
thsi one
2x-5y=-35
-5y=-2x-35
y=2/5x+7
slope=2/5
2/5 times -5/2=-1
y=-5/2x+b
findn b
(10,4)
(x,y)
4=-5/2(10)+b
4=-25+b
21=b
y=-5/2x+21
2y=-5x+42
5x+2y=42
You mark it up 20% Price + 20% = p + 20/100p = p (1 + 0.20 ) = 1.2 p
6.45 * 1.2 = 7.74
You take off 5% which by the same reasoning (almost) means p/1.05
7.74 / 1.05 = 7.37
Now you need a sales tax
7.37 * 1.06 = 7.81 dollars.
Answer: The customer paid 7.81 <<<<=====
25 is .0333% of 750
•25/750 = .03
750 is 3000% of 25
•3000% = 30
