So if 199.75 is the cost after a 18% discount
The original price is 100%
Then the price after a 18% discount is
Tell me as a percentage
There are different ways to solve a quadratic equation, the main ones that i'm thinking about right now are:
1) factor the equation as a product:
ex: x^2+ 4x + 3 =0
(x+3) (x+1) = 0
x=-3 and x=-1 are the solutions.
To find (x+p) and (x+q) you have to think that (p+q )have to be equal to the number that is multiplied by x, in my example it was 4 (3+1=4), (p times q) have to be equal to the last number of the quadratic equation, the one that is not multiplied by any x, that in my example is 3 (3 x 1= 3)
2) The other way to solve a quadratic function is by using a formula:
given: ax^2 +bx +c=0
x= (-b +/- <span>√(b^2 -</span> 4ac)) / 2a
ex: 3x^2 + 4x -2=0
x= (-4 +/- √16-4(3)(-2)) / 6= (-4 +/- √16+24)/6= (-4 +/- <span>√40) / 6
now there are 2 possibilities: x= (-4+</span><span>√40) /6
and
x= (-4 - </span><span>√40) / 6
I hope the examples were clear enough also if i did't get very nice numbers. Look closely to the sings + and -, they are very important</span>
According to my calculations the 30% of 570 is 171
10% of 570 is 57
times that by 3 and you get 171
He needs it 4 inches longer because 4 ft is 48 inches.
7(a - 10) = 13 - 2(2a + 3)
7a - 70 = 13 - 4a - 6 = 7 - 4a
7a + 4a = 7 + 70
11a = 77
a = 77/11 = 7
a = 7.
