Answer:
x=1, y=-4. (1, -4).
Step-by-step explanation:
y=-7x+3
y=-x-3
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-7x+3=-x-3
-7x-(-x)+3=-3
-7x+x=-3-3
-6x=-6
6x=6
x=6/6
x=1
y=-1-3=-4
Answer:

Step-by-step explanation:
Given


Required
Write equation in slope intercept form
An equation in slope intercept form is:

Substitute values for m and b

Answer:
1. 516 ppm; 2. 561 ppm
Step-by-step explanation:
1. CO₂ increase at old rate
Time = 2100 - 2010 = 90 years
Increase in CO₂ = 90 yr × (1.4 ppm/1 yr) = 126 ppm
CO₂ in 2010 = 390 + 126 = 516 ppm
At the old rate, the CO₂ concentration in 2100 will be 516 ppm.
2. CO₂ increase at new rate
Time = 2100 - 2010 = 90 years
Increase in CO₂ = 90 yr × (1.9 ppm/1 yr) = 171 ppm
CO₂ in 2010 = 390 + 171 = 561 ppm
At the new rate, the CO₂ concentration in 2100 will be 561 ppm.