Answer:
Plates are 2.80 Dollars and cups are 1.40 dollars
Step-by-step explanation:
Cups = c
Plates = p
6p + 5c = 23.80 ==> multiply by 6 ==> 36p + 30c = 142.80
7p + 6c = 28.00 ==> multiply by 5 ==> 35p + 30c = 140.00
Now use algebra to have the 30c be on one side and the rest on the other:
36p + 30c = 142.80 | -36p
30c = 142.80 - 36p
35p + 30c = 140.00 | -35p
30c = 140.00 - 35p
Now set them equal to each other about the 30c:
142.80 - 36p = 140.00 - 35p
Use algebra to solve for p:
142.80 - 36p = 140.00 - 35p | +36p
142.80 = 140.00 + p | - 140
2.80 = p
Go back to one of the "30c" equations and plug in the value for p:
30c = 140 - 35p
30c = 140 - 35(2.80)
30c = 140 - 98
30c = 42 | /30
c = 42/30
c = 1.4
Answer:
3.5
Step-by-step explanation:
2a + 3b = 6 --> Equation 1
5a + 2b = 4 --> Equation 2
Equation 1 * 5 --> 10a + 15b = 30
Equation 2 * 2 --> 10a + 4b = 8
Equation 1 - Equation 2 --> 11b = 22 --> b = 2
Sub b=2 in Equation 1 (or 2, either works):
2a + 3b = 6
2a + 3(2) = 6
2a + 6 = 6
2a = 0
a = 0
b = 2, a = 0
So you have 3 and you want to get rid of 2 2/5. 3-2 is 1 1-2/5 is equal to three fifths, which is the answer.
(-1.7, -4.9)
to reflect across the x-axis multiply the x-value by negative 1