Just "plug n chug" as my teacher would say. In other words, replace the letters with the values.
Choice A is (7,19) which means x = 7 and y = 19. Let's replace the x and y value with these numbers in both equations. If we get a true equation, then we found the answer.
2x-y = -5
2*7-19 = -5
14-19 = -5
-5 = -5 ... true
So that works. Let's try the other equation
x+3y = 22
7+3*19 = 22
7+57 = 22
64 = 22 ... false
So choice A is NOT the answer because of this. Let's try out choice B
2x-y = -5
2*4-9 = -5
-1 = -5 ... false
so B doesn't work either. How about C?
2x-y = -5
2*8-21 = -5
-5 = -5 ... that works
x+3y = 22
8+3*21 = 22
71 = 22 ... but this is false
So D has to be the answer. Let's check to confirm or not
2x-y = -5
2*1-7 = -5
-5 = -5 ... true
x+3y = 22
1+3*7 = 22
22 = 22 ... true
BOTH equations are true at the same time so (1,7) is definitely the final answer
So
100%=original
25% discount
100-25=75
it is 180 sale
75%=180
find 100%
a hack is to recognize that 75/3 times 4=100 so
75%=180
divide 3
25%=60
times 4
100%=240
the real way is proportions
75:180 =100:x
75/180=100/x
multiply both sides by 180x
75x=18000
divide 75
x=240
origitnal price=$240
Answer:
I did the math and got an answer of 17.5
Step-by-step explanation:
I divided 70 by 4 and got a result of 17.5. This probably means Caleb started his collection about 17 and 1/2 months ago. (I apologize if it's wrong)
Answer:
Using SAS they are congruent.
Step-by-step explanation:
E is the point where the diagonals AC and BD meet.
Side: AB = CD
Angle: ∠ABE = ∠EDC
Side: BE = DE
Hence by SAS theorem the two triangles are congruent.
By understanding and applying the characteristics of <em>piecewise</em> functions, the results are listed below:
- r (- 3) = 15
- r (- 1) = 11
- r (1) = - 7
- r (5) = 13
<h3>How to evaluate a piecewise function at given values</h3>
In this question we have a <em>piecewise</em> function formed by three expressions associated with three respective intervals. We need to evaluate the expression at a value of the <em>respective</em> interval:
<h3>r(- 3): </h3>
-3 ∈ (- ∞, -1]
r(- 3) = - 2 · (- 3) + 9
r (- 3) = 15
<h3>r(- 1):</h3>
-1 ∈ (- ∞, -1]
r(- 1) = - 2 · (- 1) + 9
r (- 1) = 11
<h3>r(1):</h3>
1 ∈ (-1, 5)
r(1) = 2 · 1² - 4 · 1 - 5
r (1) = - 7
<h3>r(5):</h3>
5 ∈ [5, + ∞)
r(5) = 4 · 5 - 7
r (5) = 13
By understanding and applying the characteristics of <em>piecewise</em> functions, the results are listed below:
- r (- 3) = 15
- r (- 1) = 11
- r (1) = - 7
- r (5) = 13
To learn more on piecewise functions: brainly.com/question/12561612
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