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)
During the 9 mile hike he spends 2 periods of half hour swimming = 1 hour.
actual hiking time = 3*3 = 9 hours
So total time = 9+1 = 10 hours
Answer:
1r
Step-by-step explanation:
(5r-4)(2r-6r+4)
1(5r-4)+1(2r-6r+4)
5r-4+2r-6r+4
5r+2r-6=1r
1r-4+4
-4+4=0
1r
Answer:
60 percent i hope this helped.
Step-by-step explanation:
each have a a possibility of 10 and there's 6 of of 10 compared to 3 out of 10.
Answer:
13/20 = 65%
Step-by-step explanation:
1/4 = 25%
7/10 = 70%
13/20 = 65%
Only the last one had the correct percentage.