Question

find the roots of quadratic equations by factorisation:-
x² - 3x - 10 = 0​

Answer 1

Resposta:

S={-2, 5}

Explicação passo-a-passo:

$x {}^{2} - 3x - 10 = 0$

a=1, b=-3 c=-10

$delta = b {}^{2} - 4ac$

$delta = ( - 3) {}^{2} - 4 \times 1 \times - 10 = 9 + 40 = 49$

$\sqrt{49} = 7$

$x1 = \frac{ - ( - 3) + 7}{2.1} = \frac{3 + 7}{2} = \frac{10}{2} = 5$

$x2 = \frac{ - ( - 3) - 7}{2.1} = \frac{3 - 7}{2} = \frac{ - 4}{2} = - 2$

Answer 2

Explicação passo-a-passo:

x² - 3x - 10 = 0

x²+2x-5x-10=0

x*(x+2)-5(x+2)=0

(x+2)*(x-5)=0

x+2=0

x=0-2

x¹=-2

x-5=0

x=0+5

x=5