9514 1404 393
Answer:
- x+y=70; 8.50x+12.50y=10.56(70)
- 36 pounds Antigua
- 34 pounds Rift
Step-by-step explanation:
At the insistence of the problem author, we will let x represent pounds of Antigua coffee and y represent pounds of Rift coffee. Then we have ...
x + y = 70
8.50x +12.50y = 10.56(70) . . . . . total cost of the mix
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We like to use the variable to represent the high-cost contributor. Here, that is y, so we'll substitute for x:
x = 70-y
8.50(70 -y) +12.50y = 10.56(70)
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595 +4y = 739.2 . . . . . . . . . . . . . . simplify
4y = 144.2 . . . . . . . . . . . subtract 595
y = 36.05 . . . . . . . divide by 4
x = 70 -36.05 = 33.95
About 36 pounds of Rift Valley coffee and 34 pounds of Gualtemala Antigua coffee must be mixed.
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<em>Additional comment</em>
By letting the variable in our equation 8.50(70 -y) +12.50y = 10.56(70) represent the high-cost coffee, we ensure that the simplified equation will have a positive coefficient for the variable. This means we don't have to mess with negative numbers, so eliminating a common source of math errors.
The problem requirement that we use x for the low-cost contributor meant we introduced an extra equation that would not have been needed.
The two graphs in the second picture are the graphs of exponential functions. You can detect it from the L shaped graphs.
The very first graph represents a linear function. A straight line always represents a linear function. In a Linear function, the change in the values of y is constant throughout in relative to change in x values.
The final graph represents a quadratic function rising on both ends.
Therefore, option b and c are the correct answers
Answer:
x axis: -1, 0, -3
Step-by-step explanation:
Answer:
B and C
2. B Multiplication property of equality
3. C Distributive Property
Step-by-step explanation:
1. Given
2. Multiply this equation by 5:
Multiplication property of equality
3. Use distributive property of equality:
4. Subtract 30:
Subtraction property of equality.
