Heather is cashier, she can ring up 12 customers in 9 minutes at this rate how many minutes does it take to ring up 4 customers
1 answer:
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Call the number of trumpet players "T" and the number of horn players "H".
We can use the given information to set up equations:
1."<span>the number of trumpet players is 4 times the number of French horn players"
2. "</span><span>There are 35 trumpet and French horn players in the band."
If you were asked to solve you could now do it by substitution:
</span>
We can use the given information to set up equations:
1."<span>the number of trumpet players is 4 times the number of French horn players"
2. "</span><span>There are 35 trumpet and French horn players in the band."
If you were asked to solve you could now do it by substitution:
Answer:
(x, y) = (1, -1)
Step-by-step explanation:
We'll write these equations in general form, then solve using the cross-multiplication method.
43x +67y +24 = 0
67x +43y -24 = 0
∆1 = (43)(43) -(67)(67) = -2640
∆2 = (67)(-24) -(43)(24) = -2640
∆3 = (24)(67) -(-24)(43) = 2640
These go into the relations ...
1/∆1 = x/∆2 = y/∆3
x = ∆2/∆1 = -2640/-2640 = 1
y = ∆3/∆1 = 2640/-2640 = -1
The solution is (x, y) = (1, -1).
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<em>Additional comment</em>
The cross multiplication method isn't taught everywhere. The attachment explains a bit about it. Our final relationship changes the order of the fractions to 1, x, y from x, y, 1. That way, we can use the equation coefficients in their original general-form order. (The fourth column in the 2×4 array of coefficients is a repeat of the first column.)
