Given:
The inequality is
To find:
The solution of the given inequality.
Solution:
We have,
Isolate the variables terms on the left side.
Divide both sides by -5 and change the inequality sign as we divide the equality by a negative value.
Therefore, the correct option is D.
Answer:
...
Step-by-step explanation:
2:4
simplified is
1:2
If you ever swam in a pool and your eyes began to sting and turn red, you felt the effects of an incorrect pH level. pH measures the concentration of hydronium ions and can be modeled by the function p(t) = −log10t. The variable t represents the amount of hydronium ions; p(t) gives the resulting pH level.
Water at 25 degrees Celsius has a pH of 7. Anything that has a pH less than 7 is called acidic, a pH above 7 is basic, or alkaline. Seawater has a pH just more than 8, whereas lemonade has a pH of approximately 3.
Create a graph of the pH function either by hand or using technology. Locate on your graph where the pH value is 0 and where it is 1. You may need to zoom in on your graph.
The pool maintenance man forgot to bring his logarithmic charts, and he needs to raise the amount of hydronium ions, t, in the pool by 0.50. To do this, he can use the graph you created. Use your graph to find the pH level if the amount of hydronium ions is raised to 0.50. Then, convert the logarithmic function into an exponential function using y for the pH.
The pool company developed new chemicals that transform the pH scale. Graph the parent pH function p(t) = −log10t and the transformations below on the same graph. Send the graph to your partner. Your partner will explain which transformation results in a y-intercept and why. You may graph by hand or using technology. Use complete sentences.
p(t) + 1
p(t + 1)
−1 • p(t)
Image by goodtextures: http://fav.me/d2he3r8
p(t)=-log(t)
p(.5)=-log(.5)= 0.3
y=-log ^(0.5)
10^-y= 0.5
10
p(t)+1
Red line on graph, this transformation has shifted up by 1. This translation doesn't result in a y-intercept.
p(t+1)
Blue line on graph, this transformation is shifting to the left by 1. This translation results in a y-intercept because it crosses the y-axis.
<span>-1 p(t) </span>
Answer: the cost of each pencil is $0.5
the cost of each eraser is $0.15
Step-by-step explanation:
Let x represent the cost of one pencil.
Let y represent the cost of one eraser.
Becky spent $1.45 for 2 pencils and 3 erasers. This means that
2x + 3y = 1.45- - - - - - - - - -1
Luke spent $2.65 for 5 pencils and 1 eraser. This means that
5x + y = 2.65- - - - - - - - - -2
Multiplying equation 1 by 1 and equation 2 by 3, it becomes
2x + 3y = 1.45
15x + 3y = 7.95
Subtracting, it becomes
- 13x = - 6.5
x = - 6.5/- 13
x = 0.5
Substituting x = 0.5 into equation 2, it becomes
5 × 0.5 + y = 2.65
2.5 + y = 2.65
y = 2.65 - 2.5
y = 0.15
