A primary source saw something first-hand. A secondary source only heard about it.
Answer:
Step-by-step explanation:
x-y=14
x-1/3y=1/10
-y=14-x
y=-14+x
take out the factors
x-10/30y=3/30
30x-10y=3
substitute
30x-10(-14+x)=3
30x+140-10x=3-140
20x/20=-137/20
x=-6.85
y=-14+(-6.85)
y=-20.85
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)
Answer:
74 pages/hour
Step-by-step explanation:
The average rate of change is the difference in the numbers of pages divided by the difference in the numbers of hours.
At the end of 3 hours, 90 pages were read.
At he end of 5 hours, 238 pages were read.
Difference in hours: 5 hours - 3 hours = 2 hours.
Difference in pages: 238 pages - 90 pages = 148 pages
The average rate of change is the difference in pages divided by the difference in hours.
average rate of change = (148 pages)/(2 hours) = 74 pages/hour
