Subtracting the second equation by 18 on both sides, we have xy=-18. Next, we divide both sides by x to get y=-18/x Plugging that into the first equation, we have x+2(-18/x)=9. Multiplying both sides by x, we get x^2-36=9x. After that, we subtract both sides by 9x to get x^2-9x-36=0. Finding 2 numbers that add up to -9 but multiply to -36, we do a bit of guess and check to find the answers to be -12 and 3. Factoring it, we get
x^2-12x+3x-36=x(x-12)+3(x-12)=(x+3)(x-12). To find the x values, we have to find out when 0=(x+3)(x-12). This is simple as when you multiply 0 with anything, it is 0. Therefore, x=-3 and 12. Plugging those into x=-18/y, we get x=-18/y and by multiplying y to both sides, we get xy=-18 and then we can divide both sides by x to get -18/x=y. Plugging -3 in, we get -18/-3=6 and by plugging 12 in we get -18/12=-1.5. Therefore, our points are (-3,6) and (12, -1.5)
Step-by-step explanation:
If the order of the cards doesn't matter:
₅₂C₅ = 52! / (5! (52−5)!)
₅₂C₅ = 2,598,960
If the order of the cards does matter:
52 × 51 × 50 × 49 × 48 = 311,875,200
Just get only one of the placeholder on one side by itself
and do the same thing to both sides so it stays equal
3x+7=5x-21
add 21 to both sides
3x+28=5x
subtract 3x from obht sides
28=2x
sivide both sides by 2
14=x
Answer:
B
) Negative
Step-by-step explanation:
Given the expression 3xy
when x>0 and y<0
The value of the expression 3xy will be negative.
This is because the product of a positive and negative number will always be negative.
For illustration,
Let x=5>0 and y=-5<0
3xy=3(5)(-5)=-75
NOTE:
Answer:
n = -1
Step-by-step explanation:
n^2 + 5n + 1 = 3n
N^2 +2n +1 = 0 (subtract 3n from both sides)
(n+1)(n+1) = 0 (factor
n+1 =0; n= -1
n+1 = 0 ; n=-1
