Answer:
x=-5/2
Step-by-step explanation:
4 x^2 +20 x +25 = 0
x^2+5x=-25/4
(b/2)^2=(5/2)^2
x^2+5x+25/4=0
(x+5/2)^2=0
x=-5/2
(Hope this helps)
Subtract 120 every time but I don’t know the second one
Hello :
cos(3<span>θ) = -1
</span>cos(3θ) = cos(<span>π)
</span>general solution in : R is
3θ = (2k+1)π k in Z
θ = (2k+1)π/3
if θ in <span> [0 , 2</span>π] the solutions are :
k=0 : x = π/3
k=1 : x = π
k=2 : x = 5π/3