Let's identify what we are looking for in terms of variables. Sandwiches are s and coffee is c. Casey buys 3 sandwiches, which is represented then by 3s, and 5 cups of coffee, which is represented by 5c. Those all put together on one bill comes to 26. So Casey's equation for his purchases is 3s + 5c = 26. Eric buys 4 sandwiches, 4s, and 2 cups of coffee, 2c, and his total purchase was 23. Eric's equation for his purchases then is 4s + 2c = 23. In order to solve for c, the cost of a cup of coffee, we need to multiply both of those bolded equations by some factor to eliminate the s's. The coefficients on the s terms are 4 and 3. 4 and 3 both go into 12 evenly, so we will multiply the first bolded equation by 4 and the second one by -3 so the s terms cancel out. 4[3s + 5c = 26] means that 12s + 20c = 104. Multiplying the second bolded equation by -3: -3[4s + 2c = 23] means that -12s - 6c = -69. The s terms cancel because 12s - 12s = 0s. We are left with a system of equations that just contain one unknown now, which is c, what we are looking to solve for. 20c = 104 and -6c = -69. Adding those together by the method of elimination (which is what we've been doing all this time), 14c = 35. That means that c = 2.5 and a cup of coffee is $2.50. There you go!
Answer:
fish camera
Step-by-step explanation:
I think I took the quiz
Answer:
So F(x+3) = (x+3+5)/2 = (x+8)/2
Step-by-step explanation:
Given F(2x-1) = x+2
Put 2x-1 = y=> x = (y+1)/2
Hence F(y) = (y+1)/2 +2 = (y+5)/2
So F(x) = (x+5)/2
So F(x+3) = (x+3+5)/2 = (x+8)/2.
When put in a calculator, the answer is 12.22 (recurring)
Answer:
Q is not the midpoint of PR
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
If Q is the midpoint of PR
then
PQ=QR
substitute the given values and solve for x
Remember that
----> given problem
substitute the value of x
Compare with the given value of PR
therefore
Q is not the midpoint of PR
