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:
5
Step-by-step explanation:
ITS 5
Answer: A. Less than 0
Step-by-step explanation:
The answer when solving it gives you
x = -1.46557113 which means it is less than 0
According to Figure that is shown below, the correct answer for this problem is:
<span>
B. They are alternate interior angles, so angle 3 also measures 130°. </span>The same happens with 7 and 11. This is an obtuse angle, that is, this kind of angles measures more than 90° but less than 180°.
3x + 2y - 4z/x for x=5, y=-2, z=10
3x + 2y - 4z/x
3(5) + 2(-2) - 4(10)/(5)
15 - 4 - 40/5
15 - 4 - 8
11 - 8
3
