X is Kevin; Y is Dan
X = 3Y
X - 4 = 5(Y - 4)
3Y - 4 = 5(Y - 4)
3Y - 4 = 5Y - 20
+ 4 +4
4 cancels each other out.
3Y = 5Y - 16
- 5 -5
5 cancels each other out.
-2Y = -16
/2 /2
Y = 8
X = 3Y;
X = 3 x 8;
Thus,
X = 24;
Kevin(x) is 24
the discriminant b^2 - 4ac when the equation is in the form of ax^2 +bx+c=0
13x^2-16x = x^2 -x
we need to get in it the standard form
subtract x^2 from each side
12x^2 -16x = -x
add x to each side
12x^2 -15x = 0
12x^2 -15x -0 =0
a=12 b=-15 c=0
b^2 -4ac
the discriminant = b^2
b^2 = (-15)2 = 225
C=3 that’s the answer I think
Answer: $20
Explanation: If you have $17.70 after 2 games and $14.25 after 5, you do 17.70-14.25; which equals $3.45 so in 3 games you spend $3.45 now divide that by 3 to determine the unit value; which equals $1.15, so you spend $1.15 on every game now times that by 2 which is $2.30 and add that to $17.70 to see the original amount of money on the card which was $20