We know that sin2x=2sinxcosx
(search the net for proof if you wish)
So the original equation becomes
2sinxcosx-sinx=0
The two terms both have sinx that can be taken out to get:
sinx(2cosx-1)=0
This is true if sinx=0 or 2cosx-1=0 , rewritten: cosx=1/2
sinx=0 than x=2kπ
cosx=1/2 than x=π/3+2kπ
where k is an integer
Answer:
linear equation has two variables doesn't involve any power
quadratic equation involves one of the variables raised to the second power.
Step-by-step explanation:
A <u>linear equation</u> in two variables doesn't involve any power higher than one for either variable. It has the general form Ax + By + C = 0, where A, B and C are constants. ... A <u>quadratic equation</u>, on the other hand, involves one of the variables raised to the second power.
The reflection over the y-axis has a rule:

From the diagram you can see that point W has coordinates (-7,2). Then using the rule given above, you can find the coordinates of point W':

Answer: (7,2).
(1) Answer : 
Step 1: 
Step 2: 
In completing the square method we take coefficient of x and divide by 2 and the square it . Then add it on both sides
The coefficient of x is -6.
= (-3)^2 = 9
The coefficient of y is -4.
= (-2)^2 = 4
Step : 
(2) 
To find center and radius we write the equation in the form of
using completing the square form
Where (h,k) is the center and 'r' is the radius


In completing the square method we take coefficient of x and divide by 2 and the square it . Then add it on both sides


Here h= -3 and k=3 and
so r= 4
Center is (-3,3) and radius = 4
(c) Step 1: 
Step 2: 
Step 3: 
Step 4: 
We factor out each quadratic
(x^2 + 8x + 16) = (x+4)(x+4) = 
((y^2 - 6y + 9)) = (x-3)(x-3) = 
Step 5 :
Answer:
21
Step-by-step explanation:
15/ 5/7 = 21