X*a = 244 is equation (1)
x+a = 2 is equation (2)
Solve equation (2) for 'a' to get
x+a = 2
a = 2-x
Call this equation (3)
We will plug equation (3) into equation (1)
x*a = 244
x*(a) = 244
x*(2-x) = 244
Notice how the 'a' is replaced with an expression in terms of x
Let's solve for x
x*(2-x) = 244
2x-x^2 = 244
x^2-2x+244 = 0
If we use the discriminant formula, d = b^2 - 4ac, then we find that...
d = b^2 - 4ac
d = (-2)^2 - 4*1*244
d = -972
indicating that there are no real number solutions to the equation x^2-2x+244 = 0
So this means that 'x' and 'a' in those two original equations are non real numbers. If you haven't learned about complex numbers yet, then the answer is simply "no solution". At this point you would stop here.
If you have learned about complex numbers, then the solution set is approximately
{x = 1 + 15.588i, a = 1 - 15.588i}
which can be found through the quadratic formula
Note: it's possible that there's a typo somewhere in the problem that your teacher gave you.
I believe the answer is 136.5g
<span>204
First, lookup a standard normal table and see what the z-score is for 0.025 (one half of 100% - 95%) to allow for equal sized tails. You should find that the z-score is 1.96. That means that 95% of the time, the value should be within 1.96 standard deviations of the mean. Now let's calculate the standard deviation.
800 is 800 - 1200 = -400 to the left of the mean of 1200.
1600 is 1600 - 1200 = 400 to the right of the mean of 1200.
So we are an equal distance of 400 on both sides of the mean. And we know from the z-score of 1.96, that we're 1.96 standard deviations from the mean. So a little division will give us the standard deviation. Which is:
400 / 1.96 = 204.0816327
So the standard deviation of the light bulbs is 204</span>
Answer: multiply the number of pounds by 16 to get number of ounces (since there isn't a number in between weighs/pounds)
