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)
Answer:
Step 3 they took the square root incorrectly
Step-by-step explanation:
5 ( x-2)^2 +6 = 86
Subtract 6 from each side
5 ( x-2)^2 +6 -6= 86-6
5 ( x-2)^2 = 80
Divide each side by 5
5 ( x-2)^2 /5 = 80/5
(x-2)^2 = 16
Take the square root of each side
sqrt((x-2)^2) = ±sqrt(16)
x-2 = ±4
To solve this problem you must apply the proccedure shown below:
1. She has a total of 50 DVDs of 90 minutes each one of them. The cost of each DVD was 11€.
2. Therefore, to calculate the total cost of the collection, you must multiply the cost of each DVD by the total number of them:
€
3. To calculate the total minutes of the collection, you must multiply 90 minutes by the total number of DVDs:
Therefore, the answer is: 550€ and 4500 minutes.
Answer:
the missing angle is 5m
Step-by-step explanation:
