X= -2 and x= 2 are the answers
Answer:
Step-by-step explanation:
At the point where two line cut across, the vertically opposite angles formed are equal. This means that
2x degrees = 78 degrees
Dividing the left hand side and the right hand side of the equation by 2, it becomes
2x/2 = 78/2
x = 39
Checking,
The sum of the angles on a straight line is 180 degrees.
180 - 78 = 102 degrees
2x + 102 = 180
2x = 180 - 102 = 78
x = 78/2 = 39
Answer: 6 large frames and 12 small frames
Step-by-step explanation:
We define the following:
x = number of large frames
y = number of small frames
Make the following equations:
x + y = 18
19x + 9y = 222
Use system of equations to solve. We find the value of x first.
y = 18 - x
⇒ 19x + 9(18 - x) = 222
⇒ 19x + 162 - 9x = 222
⇒ 10x + 162 = 222
⇒ 10x = 60
⇒ x = 6
Find value of y:
6 + y = 18
y = 12
∴ 6 large frames and 12 small frames were purchased.
