Question

(6+√-64)(3-√-16) Multiply. This is urgent, please explain this to me!

Answer 1

Answer:

50

Step-by-step explanation:

$\sqrt{-64}$ and $\sqrt{-16}$ can be expressed in complex form, with $\sqrt{-1}$ = i

$\sqrt{-64}$ = $\sqrt{64(-1)}$ = $\sqrt{64}$ × $\sqrt{-1}$ = 8i

$\sqrt{-16}$ = $\sqrt{16(-1)}$ = $\sqrt{16}$ × $\sqrt{-1}$ = 4i

the factors can then be expressed as

(6 + 8i)(3 - 4i) ← expand using FOIL

= 18 - 24i + 24i - 32i² [ i² = ($\sqrt{-1}$ )² = - 1 ]

= 18 - 24i + 24i + 32 ← collect like terms

= 18 + 32 + 0

= 50