Answer:
Sarah will have $200 after 3 weeks
Step-by-step explanation:
amount saved at the start = $20
amount saved per week = $10
number of weeks = 3
∴ Total savings from allowance after 3 weeks = 10 × 3 = $30
Amount received in birthday money = $150
∴ Total amount saved after 3 weeks = amount saved at the start + Total savings from allowance after 3 weeks + Amount received in birthday money
Total amount saved after 3 weeks = 20 + 30 + 150 = $200
Therefore Sarah will have $200 after 3 weeks
He made a mistake in step #2. It seemed to be a trivial mistake because it involved signs, but it still had a great impact. Since step#2, his solution was already wrong.
Instead of
(-1)²-4(2)(-6) = 1 + 48 = 49
What he did is
(-1)²-4(2)(-6) = -1 + 48 = 47
Answer:
$178.3
Step-by-step explanation:
The value of a car is $20,000
The car loses 10.7% of its value yearly
Since there are 12 months in a year then 10.7% can be represented as
10.7%/12
= 0.8916%
Therefore the approximate monthly decrease in value can be calculated as follows
= $20,000×0.8916/100
= $20,000×0.008916
= $178.3
Hence the approximate monthly decrease in value is $178.3
Answer:
The axis of symmetry is x = 6
Step-by-step explanation:
To find this, first find the two x-intercept values and then take the average. This will always be the line of symmetry.
x + 9 = 0
x = -9
x - 21 = 0
x = 21
Now take the average of these two numbers.
(-9 + 21)/2
12/2
6