If you know that -2 is a zero of f(x) = x^3 + 7x^2 + 4x - 12, explain how to solve the equation.
First you have to figure out what could make f(x) = 0 to get rid of the cube. I'm going to test the array of data, x = -2, x = -3, and x = -4 because this type of equation probably has more negative values given that if you plug in some values the cubed-values and squared-values will surpass the "-12". Plug this into a calculator.
x^3 + 7x^2 + 4x - 12
f(-2) = -8 + 28 - 8 - 12 = 0
So you know that when x = -2, f(x) = 0. Divide "(x + 2)" from the equation and you will get... x^2 + 5x - 6. Now this is a simple polynomial one that you can figure to be (x + 6) (x - 1) just by looking at it because -6 multiplied by 1 is negative 6 and you see 5 and know that 6 - 1 = 5.
The solution is (x + 6) (x - 1) (x + 2) meaning that when x = -6, 1, or -2, f(x) is 0.
Answer:
its b
Step-by-step explanation:
i did this
For each of these problems, remember SOH-CAH-TOA.
Sine = opposite/hypotenuse
Cosine = adjacent/hypotenuse
Tangent = opposite/adjacent
5) Here we are looking for the cosine of the 30 degree angle. Cosine uses the adjacent side to the angle over the hypotenuse. Therefore, cos(30) = 43/50.
6) We have an unknown side length, of which is adjacent to 22 degrees, and the length of the hypotenuse. Since we know the adjacent side and the hypotenuse, we should use Cosine. Therefore, our equation to find the missing side length is cos(22) = x / 15.
7) When finding an angle, we always use the inverse of the trigonometry function we originally used. Therefore, if sin(A) = 12/15, then the inverse of that would be sin^-1 (12/15) = A.
8) We are again using an inverse trigonometry function here. We know the hypotenuse, as well as the side adjacent to the angle. Therefore, we should use the inverse cosine function. Using the inverse cosine function gives us cos^-1 (9/13) = 46 degrees.
Hope this helps!
Given:
John had to pay a combined electric and gas bill $150.
The electric portion of the bill was $90.
To find:
The ratio of money spent on electric to that on gas.
Solution:
Let x be the amount of gas bill.
The electric portion of the bill was $90 and John had to pay a combined electric and gas bill $150. So,
The gas portion of the bill was $60.
The ratio of money spent on electric to that on gas is:
Therefore, the ratio of money spent on electric to that on gas is 3:2.