You can use the sum and difference identities which for cosine is cos(a+b)= cosacosb-sinasinb
Use the slope formula (y2-y1)/(x2-x1)
(0+9)/(4+7)=9/11
Since q is parallel to r the slope will be the same. 9/11 is the slope of line r
Point A is (-3,1), C is (4,4)
MidPoint is ( (x1+x2)/2, (y1+y2)/2)
MP is (0.5, 2.5)
x^2 -12 x = -28
(-12/2) ^ 2 =36
x^2 -12 x + 36 = -28 + 36
x^2 -12x + 36 = 8
(x-6)^2 = 8
take the square root of each side
x-6 = sqrt (8) x-6 = -sqrt (8)
you get a positive and a negative when taking the square root
x= 6 + sqrt (8)
x = 6 - sqrt (8)
sqrt (8) = 2 sqrt (2)
x= 6 + 2 sqrt (2)
x = 6 - 2 sqrt (2)
Answer:
x= 6 + 2 sqrt (2)
x = 6 - 2 sqrt (2)
