Answer: $31.99
Step-by-step explanation:
So, it is originally $39.99, so first we convert 20% to a decimal, which is 0.2.
Then we do 39.99 * 0.2 to find how much money was taken off.
39.99 * 0.2 = 7.998, or $8
Now, we do the original dollar amount, $39.99, minus the discount, $8, which equals $31.99.
7/8+9/10=71/40=1 31/40
1/4+2/3=11/12
1/2+1/4 is different from 1/2+1/3 because
1/2+1/4= 2/4+1/4= 5/1 =1 1/4
1/2+1/3=3/6+2/6=5/6
First lets distribute the 5x
5x^2 + 30x = -50
Lets divide every term by 5
x^2 + 6x = -10
To complete the square we have to half the b value, which in this case is 6. Then square it.
Half of 6 is 3, 3 squared is 9
Add that to both sides of the equation
x^2 + 6x + 9 = -1
Find the binomial squared
(x+3)^2 (If you're wondering how i got that please comment)
(x+3)^2 = -1
Take the square root of the equation of both sides
(x+3) = +/- i
x = -3 +/- i
x = -3 - i
and
x = -3 + i
45 divided by 5 is 9 and 9 times 8 is 72 so the answer is 72.
