Answer:
x = -3
Step-by-step explanation:
3(x - 6)= -2 + 5(2x + 1)
= 3x - 18 = -2 + 10x + 5
= -18 = -2 + 7x + 5
= -18 = 7x + 3
= -21 = 7x
= -3 = x
= x = -3
<span>B. square
</span><span>C. Draw arcs on the circle with the compass set at r units.
</span>
Solution:
<u>Note that:</u>
- Han's house = 450 m from school
- Lin's house = (450 - 135) from school
<u>Looking at the options, we can tell that the letter "z" represents Lin. </u>
- => z = (450 - 135)
- => z = 450 - 135
This option matches with Option D.
Option D is correct.
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.
3/4 = x / 7.5
4x = 3(7.5)
4x = 22.5
x = 5.625