The rate of change in this pattern is 2:1 comparing the change in 'y' to the change in 'x'.. this means that if you go form 33 to 51 ( an increase of 18), then the the increase from 16 to ? will be 9. Therefore, ? = 16 + 9 or 25
? = 25
When y varies inversely as x ⇒ y*x=k
y=27 and x=40 ⇒27*40=1080=k
y*10=1080
y=1080:10
y=108
(1, 3) represent a solution to the equation.
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!!
Expressions you could use: 5(z) or 5z
