Answer:
y=2x-5
Step-by-step explanation:
The slope-intercept form of an equation looks like y=mx+b. Where m is the slope and b is the y-intercept. The slope is already given to us, so m is 2.
To find b use the equation 
. So, to find the y-intercept use b=-7-(2*-1). This equals b=-5.
So, plug in the values to get the final equation y=2x-5.
Let x be the expected number
Number arriving = 3•5 x
Unexpected number 2•5 x
2•5 x = 105
10x = 420
x = 42______Option D
12. Make equation and plug in
13. Proportion
14. Finding a constant rate, and then manipulate
12. Where x is miles driven, and y is answer, and z is days
19.95z+0.15x=y
Plug in two values
19.95 x 2 + 0.15 x 250 = y
39.93+37.5 = y
y=77.43
13. 5:2 as 175:x
5/2 = 175/x
x = 70
70+175=245
14. 260:5 = x:1
260/5=x/1
x = 52
52:1 = y:9
52/1 = y/9
y = 468
I hope you understand the process.
Answer:
about 70 years
Step-by-step explanation:
Life expectancy (e) improves by 5.7 years every 10 years, so 5.7/10 = 0.57 years per year. For t years after 2009, it can be modeled by ...
e = 0.57t +80
We want to find when that is 120:
120 = 0.57t +80
40 = 0.57t
40/0.57 = t ≈ 70.2
About 70 years from 2009, humanity may achieve a life expectancy of 120 years.
