Answer: Choice B
(-2, 5)
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Explanation:
The original system is

Multiply both sides of the second equation by 3. Doing so leads to this updated system of equations

Now add straight down
The x terms add to -4x+3x = -1x = -x
The y terms add to 3y+(-3y) = 0y = 0
The terms on the right hand sides add to 23+(-21) = 2
We end up with the equation -x = 2 which solves to x = -2
Now use this to find y. You can pick any equation with x,y in it
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-4x+3y = 23
-4(-2)+3y = 23
8+3y = 23
3y = 23-8
3y = 15
y = 15/3
y = 5
Or
x-y = -7
-2-y = -7
-y = -7+2
y = -5
y = 5
Either way, we get the same y value.
So that's why the solution is (x,y) = (-2, 5)
Answer:
$57

Step-by-step explanation:
Given that:
Earnings per hour for washing cars = $9
Earnings per hour for walking dogs = $6
Number of hours for which car washing is done = 
Number of hours taken for walking dogs = 
Earnings for
hours for washing cars = Per hour earnings multiplied by number of hours = $9
Earnings for
hours for walking dogs = Per hour earnings multiplied by number of hours = $6
Total earnings by both = $(
)
Now, given that
Number of hours spent washing cars = 5 hours
Number of hours spent walking dogs = 2 hours
Therefore, total earnings by both = 9
5 + 6
2 = <em>$57</em>
Answer:
Step-by-step explanation:
J
Answer:
For the yes/no bit:
step 1: no
step 2: no
step 3: yes
step 4: yes
step 5: no
for the final answer bit: a = 2 3/5 (the last option)
Step-by-step explanation:
yes/no bit:
step 1 is wrong because she didn't multiply
by -2
step 2 is wrong because she subtracted 1/2 instead of adding it
step 3 is correct because 6 - 1/2 = 11/2
step 4 is correct because she correctly multiplied both sides by 4
step 5 is wrong because she added 5 instead of dividing by -5.
for the final answer bit, I've attached an image below with my working out. hope this helps!
Answer:
Step-by-step explanation:
Range = difference between the highest and the lowest
Mode = Data that occurs the most time
Median = Arrange the data in ascending order. The middle data is the median. If number of data is even, median is the average of the two middle terms.
1) Range = 28 -21 = 7
Mode = 25
Number of data (Count the total dots) = 14
Median = average of 7th and 8th term
Median = (25+25)/2 = 50/2 = 25
2) Range = 0.18 - 0.11 = 0.07
Mode = 0.15 and 0.16
Number of data = 23
Median =12th term = 0.15