Answer:
I think it is of the last option
Answer: She started with $160.
It will take 6 weeks before she has less than half of what she originally invested.
Step-by-step explanation:
If her money is decreasing in value by 11% each week, it means that the rate at which it is decreasing is exponential.
We would apply the formula for exponential decay which is expressed as
A = P(1 - r)^t
Where
A represents the value of the investment after t weeks.
t represents the number of weeks.
P represents the initial value of the investment.
r represents rate of depreciation.
From the information given,
A = $142.40
r = 11% = 11/100 = 0.11
t = 1
Therefore
142.40 = P(1 - 0.11)^1
142.40 = P(0.89)
P = 142.4/0.89
P = 160
For her to have half of what she invested originally, then
80 = 160(0.89)^t
80/160 = (0.89)^t
0.5 = (0.89)^t
Taking log of both sides to base 10
Log 0.5 = log0.89^t = tlog0.89
- 0.3010 = - 0.051t
t = - 0.3010/- 0.051
t = 5.9
Approximately 6 weeks
Answer:
(-4, -5) it gives the answer in the question
Step-by-step explanation:
Answer:
19b-4
Step-by-step explanation:
7b+3(4b-2)+6÷3
Bracket comes first so we distribute 3 over the terms in the bracket
= 7b + 12b -6 +6 ÷ 3
First we solve division
= 7b + 12b -6 +6 ÷ 3
= 7b + 12b -6 +2
= (7b+12b)+(-6+2)
= 19b -4
This can't be simplified further as it can't be solved anymore
<h3>Answer: Choice D</h3>
4x - 3y = 15
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Explanation:
The two points (-1,-1) and (2,3) are marked on the line
Let's find the slope of the line through those two points.
The slope is 4/3 meaning we go up 4 and to the right 3.
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Parallel lines have equal slopes, but different y intercepts. We'll need to see which of the four answer choices have a slope of 4/3.
Solve the equation in choice A for y. The goal is to get it into y = mx+b form so we can determine the slope m.
Equation A has a slope of -3/4 and not 4/3 like we want.
Therefore, this answer choice is crossed off the list.
Follow similar steps for choices B through D. I'll show the slopes of each so you can check your work.
- slope of equation B is 3/4
- slope of equation C is -4/3
- slope of equation D is 4/3
We have a match with equation D. Therefore, the equation 4x-3y = 15 is parallel to the given line shown in the graph.
You can use graphing tools like Desmos or GeoGebra to confirm the answer.
