Question

Please help me solve question 5.) with the letters a) & b)

Answer 1

Answer:

Step-by-step explanation:

5.(a)

x²+6x-15=0

$x=\frac{-6\pm\sqrt{36+4*15}}{2*1}\\x=\frac{-6\pm\sqrt{36+60} }{2}\\x=\frac{-6\pm\sqrt{96} }{2}\\x=\frac{-6\pm4\sqrt{6} }{2}\\x=-3\pm2\sqrt{6}$

(b)

4x²-8x-1=0

$x=\frac{8\pm\sqrt{64+4*4}}{2*4}\\x=\frac{8\pm\sqrt{80}}{8}\\x=\frac{8\pm 4\sqrt{5} }{8}\\x=\frac{2\pm\sqrt{5}}{2}$