Answer:
The domain is the set of all the values of x, so it would be -3, -5, -6, -9, 0. The range would be every set of y, so it would be 7, -8, -1, -3. Finally, this relation is indeed a function.
Domain: -3, -5, -6, -9, 0
Range: 7, -8, -1, -3
Is it a function? Yes
Answer:
The slope is -3/4
Step-by-step explanation:
We need two points to find the slope
We have one point at (0,5) and we have one point at (4,2)
We can use the slope formula
m = (y2-y2)/(x2-x1)
= (2-5)/( 4-0)
= -3/4
The slope is -3/4
This is one pathway to prove the identity.
Part 1
Part 2
Part 3
As the steps above show, the goal is to get both sides be the same identical expression. You should only work with one side to transform it into the other. In this case, the left side transforms while the right side stays fixed the entire time. The general rule is that you should convert the more complicated expression into a simpler form.
We use other previously established or proven trig identities to work through the steps. For example, I used the pythagorean identity in the second to last step. I broke the steps into three parts to hopefully make it more manageable.
It sounds like everything is being described in reference to angle A, so a good starting point is to pick a variable to represent the measure of angle A. I'm going to use "a" for that.
Next, I'm going to take the verbal descriptions in the problem and "translate" them into "math language". They say angle B is 5 times angle A, so that means the measure of angle B is actually 5a. The size of angle C is 5 degrees less than 4 times the size of A, so that translates to 4a-5.
We now know the following:
Angle A: a
Angle B: 5a
Angle C: 4a-5
Now, to find the value of a, we need to remember that all the angles in a triangle add up to 180 degrees.
So we have: a+5a+4a-5 = 180
We can solve that equation by combining like terms to get: 10a-5=180
We can add 5 to both sides: 10a =185
And divide by 10: a = 18.5
That tells us the measure of angle A! (It's 18.5 degrees). Now we can go back and find B by multiplying A by 5. We get 92.5 degrees for that.
Finally, we can find C by taking 4*18.5-5. We get 69 degrees for that.
One last thing-- let's check that they really do add up to 180! 69+92.5+18.5 = 180. Yep!
Hope that helps you!!
Answer:
x = ±20
Step-by-step explanation:
x^2 -1=399
Add 1 to each side
x^2 = 399+1
x^2 = 400
Take the square root of each side
sqrt(x^2) = ±sqrt(400)
x = ±20