6-4+2x=0
2+2x=0
-2(-1-x)=0
Step-by-step explanation:
not possible
Answer:
x=6
Step-by-step explanation:
-3x=-2x-6
-3x+2x=-6
-x=-6
x=6
Answer:
0.5
Step-by-step explanation:
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:
Step-by-step explanation:
1. Since, it is given that ABCD is a parallelogram, therefore opposite angles of parallelogram are equal, hence
∠B=∠D
⇒7x-31=5x+13
⇒2x=44
⇒x=22
Hence, option B is correct.
2. Since, we get x=22, therefore
∠B=7x-31=7(22)-31=154-31=123°
∠B=123°
and ∠D=5x+13=5(22)+13=123°
∠D=123°
Also, ∠A+∠D=180°(corresponding angles)
⇒∠A=180-123
⇒∠A=57°
Now, ∠A=∠C=57°(opposite angles of parallelogram)
thus, Two of the angles measure 57°, and the other two measure 123°.
Therefore, option A is correct.