Answer:
x = approx. 1.24 or -7.24
Step-by-step explanation:
It's hard to factor directly so we should use the quadratic formula or complete the square. I'm going to go with completing the square.
x²+6x-9=0
x²+6x=9
x²+6x is the same as x²+2·3·x, in order to make this into the algebraic identity (A+B)²=A²+2AB+B², we must add B², or in this case 3² to both sides. (A is x, B is 3)
x²+6x+9=18
(x+3)²= 18
x+3= ±√18
x= ±4.24 -3 (approximately 4.24)
First solution for x = 4.24-3 = 1.24
Second solution for x = -4.24-3 = -7.24
4y is your answer because ffor is the mathmatical term for multiplying in any word problem.
The answer is D. 18.5
How? Because you have the numbers in order and cross the out it leaves you with 17, and 20 and the number between can be 19 or 18.5.
Hope I helped
Mark as brainliest?
Answer:
Step-by-step explanation:
Hello!
The variable of interest, X: height of women at a college, has an approximately normal distribution with mean μ= 65 inches and standard deviation σ= 1.5 inches.
You need to look for the value of height that marks the bottom 20% of the distribution, i.e. the height at the 20th percentile of the normal curve, symbolically:
P(X≤x₀)= 0.20
To know what value of height belongs to the 20% of the distribution, you have to work using the standard normal distribution and then reverse the standardization with the population mean and standard deviation to reach the value of X. So the first step is to look for the Z-value that accumulates 20% of the distribution:
P(Z≤z₀)=0.20
z₀= -0.842
z₀= (x₀-μ)/σ
z₀*σ= (x₀-μ)
x₀= (z₀*σ)+μ
x₀= (-0.842*1.5)+65
x₀= 63.737 inches
I hope it helps!
Answer:
8, 10, 3
Step-by-step explanation:
For finding real solutions to cubic equations and those of higher degree, I find a graphing calculator to be useful. The problem can be cast in the form ...
f(x) = 0
where f(x) is the difference between the product of the integers and 240:
f(x) = x(x +2)(x -5) -240
Then all we need to do is ask the calculator to show the x-intercept. It is x=8.
So, the three integers are ...