<span>Let x = first number
Let y = second number
x + y = 4
x * y = (-12)
Solve the first equation for x.
x = 4 - y
Now substitute this value of x into the second equation.
(4 - y) * y = (-12)
4y - y² = (-12)
y² - 4y - 12 = 0
(y + 2) * (y - 6) = 0
Now set both polynomials equal to zero
y + 2 = 0
y = -2
y - 6 = 0
y = 6
If you substituted these two values for y into either equation and solve for x, you would get the combination of 6 and -2
Hope I was able to help you! :)
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The answer is Its 55% of 200
Answer:
Yes!!!
Step-by-step explanation:
If you simplify 4/10 you will get 2/5. This means that they are equal :)
The answer is y^-1 :) when you have two exponents over a y in a fraction or divison, you always subtract the top from the bottom. hope this helps!
Answer:
Step-by-step explanation:
Hello!
You have to estimate the mean length of 4000 b.c. human skulls trough a 95% confidence interval.
You know that
n= 6 human skulls
= 94.2mm
S= 4.9
Assuming that the variable X: length of a 4000b.c. human skull (mm) has a normal distribution, to construct the interval you have to use the t statistic:
[ ± ]
[94.2 ± 2.571 * ]
[89.06; 99.34]mm
With a 95% confidence level you'd expect the interval [89.06; 99.34]mm to contain the value for the average skull length for humans 4000 b.c.
I hope this helps!