65 pts asap will mark

michele correctly solved a quadratic equation using the quadratic formula as shown below.

x=)+(square root (-5)2-4()/2)(7)

which could be the equation michele solved?
a. 7x2-5x+6=-8
b. 7x2-5x+3=5
c. 7x2-5x-2=-1
d. 7x2-5x+5=3

Step-by-step explanation:

always remember some basic principles when dealing with percentages :

100% is the whole

1% = 100%/100

n% = n×1% = n×100%/100

therefore, n% of an amount m is n/100 × m.

like 25% = 25/100 × m = 0.25 × m

so, now it should be very easy :

the 25% discount of $80 is

0.25×80

the amount deducted by (= after) the discount is

80 - 0.25×80

which is actually 0.75×80

a markup is added into the total cost incurred by the producer of a good or service in order to cover the costs of doing business and create a profit. so, a markup of 40% is simply again

0.40×80

and the sale price including (= after) the markup is then

80 + 0.40×80