The correct answer is letter D, Region D contains the solution for the system of inequalities.
If you factor the equation you can see what the solutions are. Two factor a quadratic of the form ax^2+bx+c, find two values which satisfy two conditions...
jk=ac=-15 and j+k=b=-2 so j and k must be -5 and 3 so the factors are:
(x-5)(x+3)
So the other solution is x=5
The <em>correct answer</em> is:
He paid the correct amount.
Explanation:
First we find the subtotal of Manny's items:
32.65+3(14.89)+39.99 = 32.65+44.67+39.99 = 117.31
Next, we calculate the discount. If he gets 10% off, this means he pays 100%-10% = 90% of the total. 90% = 90/100 = 0.9:
0.9(117.31) = 105.579
Next we calculate the tax. Since tax is 8%, this means he pays 100% of his subtotal after discount plus the 8% tax; 100%+8% = 108%; 108% = 108/100 = 1.08:
1.08(105.579) = 114.02532 ≈ 114.03
Since this is what he paid, he paid the correct amount.
