How to get answer for number 1: | 4+2i |

How to get answer for number 2: | 5-i |

Number 3 how to get answer: | -3i |
![\left|a+bi\right|\:=\sqrt{\left(a+bi\right)\left(a-bi\right)}=\sqrt{a^2+b^2}\\\mathrm{With\:}a=0,\:b=-3\\=\sqrt{0^2+\left(-3\right)^2}\\Refine\\=\sqrt{9}\\\sqrt{9}\\\mathrm{Factor\:the\:number:\:}\:9=3^2\\=\sqrt{3^2}\\\mathrm{Apply\:radical\:rule}:\quad \sqrt[n]{a^n}=a\\\sqrt{3^2}=3\\= 3](https://tex.z-dn.net/?f=%5Cleft%7Ca%2Bbi%5Cright%7C%5C%3A%3D%5Csqrt%7B%5Cleft%28a%2Bbi%5Cright%29%5Cleft%28a-bi%5Cright%29%7D%3D%5Csqrt%7Ba%5E2%2Bb%5E2%7D%5C%5C%5Cmathrm%7BWith%5C%3A%7Da%3D0%2C%5C%3Ab%3D-3%5C%5C%3D%5Csqrt%7B0%5E2%2B%5Cleft%28-3%5Cright%29%5E2%7D%5C%5CRefine%5C%5C%3D%5Csqrt%7B9%7D%5C%5C%5Csqrt%7B9%7D%5C%5C%5Cmathrm%7BFactor%5C%3Athe%5C%3Anumber%3A%5C%3A%7D%5C%3A9%3D3%5E2%5C%5C%3D%5Csqrt%7B3%5E2%7D%5C%5C%5Cmathrm%7BApply%5C%3Aradical%5C%3Arule%7D%3A%5Cquad%20%5Csqrt%5Bn%5D%7Ba%5En%7D%3Da%5C%5C%5Csqrt%7B3%5E2%7D%3D3%5C%5C%3D%203)
The amount of water that is needed to fill the pool is equal to the volume of the pool.
The pool is rectangular, with uniform depth so the volume of pool will be the product of its length , width and depth.
Thus,
Volume = 25 x 18 x 6 = 2700 ft³
This means, 2700 ft³ water is needed to fill the pool.
y = x³ + 3x² - x - 3
0 = x³ + 3x² - x - 3
0 = x²(x) + x²(3) - 1(x) - 1(3)
0 = x²(x + 3) - 1(x + 3)
0 = (x² - 1)(x + 3)
0 = (x² + x - x - 1)(x + 3)
0 = (x(x) + x(1) - 1(x) - 1(1))(x + 3)
0 = (x(x + 1) - 1(x + 1))(x + 3)
0 = (x - 1)(x + 1)(x + 3)
0 = x - 1 or 0 = x + 1 or 0 = x + 3
+ 1 + 1 - 1 - 1 - 3 - 3
1 = x or -1 = x or -3 = x
Solution Set: {-3, -1, 1}
Number 6 is 10:10 The first plane arrives at 6:50 you add 50 minutes to that and keep adding 50 minutes until you get to after 10:00 because it says his plane arrived after 10:00.