Since you know that PQ=RQ, you have an equilateral triangle. This makes things very simple.
Angle R should be the same as angle P.
A triangle is equal to 180 degrees.
Add angles P and R. Subtract 180 from the answer you got. That will give you 2a. a divided by 2 will give you a.
Or, since there are two right triangles, you can add 47 and 90. Subtract 180 from that and you will get a.
Answer:
c=80
Step-by-step explanation:
Based on my reading the critical damping occurs when the discriminant of the quadratic characteristic equation is 0.
So let's see that characteristic equation:
20r^2+cr+80=0
The discriminant can be found by calculating b^2-4aC of ar^2+br+C=0.
a=20
b=c
C=80
c^2-4(20)(80)
We want this to be 0.
c^2-4(20)(80)=0
Simplify:
c^2-6400=0
Add 6400 on both sides:
c^2=6400
Take square root of both sides:
c=80 or c=-80
Based on further reading damping equations in form
ay′′+by′+Cy=0
should have positive coefficients with b also having the possibility of being zero.
0.68 = 0.6 + .08 = 6 x 0.1 + 8 x .01
They should all equal 0.68 :)
Answer:
<h2>49</h2>
Step-by-step explanation:
Use PEMDAS:
P Parentheses first
E Exponents (ie Powers and Square Roots, etc.)
MD Multiplication and Division (left-to-right)
AS Addition and Subtraction (left-to-right)
==============================================
(-5)² - 2 × (-9) + 6 <em>first </em><em>E</em><em>xponents</em>
25 - 2 × (-9) + 6 <em>next </em><em>M</em><em>ultiplication</em>
25 + 18 + 6 <em>next </em><em>A</em><em>ddition</em>
43 + 6 = 49