many solutions
x + 4x = 05x = 0x = 0/5x = 0
16x2 + 8x + 1 = 0 : This factorises to (4x + 1)(4x + 1) = 0 When 4x + 1 = 0 then 4x = -1 : x = -1/4.
4x+7=9x+7 -5x=0 x=0
No.
x = -½
many solutions
x + 4x = 05x = 0x = 0/5x = 0
16x2 + 8x + 1 = 0 : This factorises to (4x + 1)(4x + 1) = 0 When 4x + 1 = 0 then 4x = -1 : x = -1/4.
4x+7=9x+7 -5x=0 x=0
No.
x^2+4x+7
8 + y = 4x8 + y - 4x = 4x - 4x 8 + y - 4x = 0 8 - 4x + y = 0
x2 + 4x + 3 = 0 (x + 1)(x + 3) = 0 x ∈ {-3, -1}
4(x + 1) = 0.
4x-y+7=0
4x + 3y=9 x=0 y=3