Answer:
The soda costs 2.20 and the sandwich costs 7.70
Step-by-step explanation:
To find this, set the soda cost as x. We now know that the sandwich cost is 3.5x. Add these together and set equal to 9.90
x + 3.5x = 9.90
4.5x = 9.90
x = 2.20
This is the cost of the soda. Now we can multiply that by 3.5 to get the sandwich cost.
3.5 * 2.20 = 7.70
There are many ways to solve simultaneous linear equations. One of my favorite for finding integer solutions is graphing. The attached graph shows the solution to be ...
... (x, y) = (4, 7)
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You can also use Cramer's Rule, or the Vedic math variation of it, which tells you the solution to

is given by

Here, that means
... x = (9·67-5·75)/(9·8-5·3) = 228/57 = 4
... y = (75·8-67·3)/57 = 399/57 = 7
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A (graphing) calculator greatly facilitates either of these approaches.
Answer:
14
Step-by-step explanation:
hope this helps
4 (k-6)-(3k+2)=-5
4k-24-3k-2=-5
k-26=-5
k=21