Answer:
- <u>120 pens and 200 pencils.</u>
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Explanation:
You can set a system of two equations.
<u>1. Variables</u>
<u />
- x: number of pens
- y: number of pencils
<u>2. Cost</u>
- <em>each pen costs</em> $1, then x pens costs: x
- <em>each pencil costs</em> $0.5, then y pencil costs: 0.5y
- Then, the total cost is: x + 0.5y
- The cost of the whole purchase was $ 220, then the first equation is:
x + 0.5y = 220 ↔ equation (1)
<u>3. </u><em><u>There were 80 more pencils than pens</u></em>
Then:
pencils = 80 + pens
↓ ↓
y = 80 + x ↔ equation (2)
<u>4. Solve the system</u>
i) Substitute the equation (2) into the equation (1):
ii) Solve
iii) Substitute x = 120 into the equation (2)
Solution: 120 pens and 200 pencils ← answer
The answer is true as the y value of y=sin
we will check each options
option-A:
For solving any equations , we always isolate variables on anyone side
For exp: x+7=1
so, this is TRUE
option-B:
For solving system of equations
For exp:
x-y=1
x+y=3
If we use addition , we could easily solve for x and y
so, this is TRUE
option-C:
We always solve problems using conventional method
we do not guess
so, this is FALSE
option-D:
We often reverse order of operation
For exp:
(x-2)^2-3=0
so, this is TRUE
option-E:
For linear equations , we always get one solution , infinite solutions or no solutions
so, this is FALSE
the diameter of two tortillas would be 6, since 12+12=24. the diameter of 24 is 6, so that would be your answer....
Answer: x = 1 + 0.5c
Step-by-step explanation:
