Question

Calculati,folosind formule de calcul prescurtat.(x+5)²;

Answer 1

$(x+5)^{2}= x^{2} +2\cdot5\cdot x+ 5^{2} = x^{2} +10x+25$

Answer 2

(x+5)²=x²+2*5*x+5²=x²+10x+25
Δ=b²-4ac=100-4*1*25=100-100=0
x₁=x₂=(-b)/2a=(-10)/2=-5