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:
I think its 5
Step-by-step explanation:
<span>The interest earned in 10 years is B. $739.97.</span>
Answer:
9(n + 22) ≤ -15
Step-by-step explanation:
9 times the sum of a number and 22 is at most −15
Let n = number
Times = multiplication
Sum = Addition
9 * n + 22
We must add parenthesis on the end on 22 and before n
We must do this because it says 9 times the sum of a number and 22 which means that 9 is being multiplied by both n and 22
We would have 9(n + 22)
9(n + 22) is at most -15
At most meaning that -15 is the highest number that 9(n + 22) can equal
Because it says at most 9(n + 22) can equal -15 or anything less than -15
So at most can be replaced with ≤
9(n + 22) ≤ -15
Answer:.OA. -4
Step-by-step explanation: