Question

dau coroana si PUNCTE !URGENT
Rezolvati prin forma redusa ecatiile de gradu II
e) x la adoua +6x-40=0
d) x la adoua - 4x-21=0
g) x la adoua +8x+7=0

Answer 1

e) x ² +6x-40=0
(x-6)(x+10)=0
Δ=b²-4ac=36+160=196=14²
x₁₂=-b-√Δ/2a
x₁=4
x₂=-10



d) x ²- 4x-21=0
(x-7)(x+3)=0
Δ=b²-4ac=16+84=100=10²
x₁₂=-b-√Δ/2a
x₁=7
x₂=-3


g) x ²+8x+7=0
(x+7)(x+1)=0
Δ=b²-4ac=64-28=36=6²
x₁₂=-b-√Δ/2a
x₁=-7
x₂=-1