Question

Me ajudem pufavor...​

Answer 1

Explicação passo-a-passo:

${x}^{2} - 8x + 15 = 0$

$x = \frac{ - ( - 8)± \sqrt{ {( - 8)}^{2} - 4 \times 1 \times 15 } }{2 \times 1}$

$x = \frac{ - ( - 8)± \sqrt{ {( - 8)}^{2} - 4 \times 15} }{2 \times 1}$

$x = \frac{ - ( - 8)± \sqrt{ {( - 8) }^{2} - 4 \times 15} }{2}$

$x = \frac{8± \sqrt{ {( - 8)}^{2} - 4 \times 15} }{2}$

$x = \frac{8± \sqrt{64 - 4 \times 15} }{2}$

$x = \frac{8± \sqrt{64 - 60} }{2}$

$x = \frac{8± \sqrt{4} }{2}$

$x = \frac{8±2}{2}$

$x = \frac{8 + 2}{2} \\ x = \frac{8 - 2}{2}$

$x = 5 \\ x = 3$

$\boxed{ x_{1} = 3} \\ \boxed{ x_{2} = 5}$

ATT:ARMANDO