Answer:
x = friends that paid discount price = 8
y = friends that paid regular price = 4
Step-by-step explanation:
Let
x = friends that paid discount price
y = friends that paid regular price
x + y = 12 (1)
6x + 8y = 80 (2)
From (1)
x = 12 - y
Substitute x = 12 - y into (2)
6x + 8y = 80 (2)
6(12 - y) + 8y = 80
72 - 6y + 8y = 80
- 6y + 8y = 80 - 72
2y = 8
y = 8/2
y = 4
Substitute y = 4 into (1)
x + y = 12 (1)
x + 4 = 12
x = 12 - 4
x = 8
x = friends that paid discount price = 8
y = friends that paid regular price = 4
Answer:
y = -2x + 1
Step-by-step explanation:
Y2 - Y1 / X2 - X1
-3 - 1 / 2 - 0
-4 / 2
= -2
y = -2x + b
-3 = -2(2) + b
-3 = -4 + b
1 = b
y = -2x + 1
Multiply the first equation by -1
-3x-y=-4
2x+y=5
Add them up
-x=1
So x=-1
And y=7
So the first option is correct
Answer:
28
Step-by-step explanation:
If a line is parallel to another, the slopes of both lines are the same. So for this problem, you can infer that the slope of the line you're trying to find is 3.
To find the actual equation of the line, you can use the given coordinates and plug them into the point slope form:
y - y1 = m(x - x1)
plug the given y coordinate into y1 and the given x coordinate into x1. m is the slope, so plug in 3 for m.
y - 1 = 3(x +2) Use distributive property for right side of equation
y - 1 = 3x + 6 add 1 to both sides to cancel -1 on left side of equation and isolate y
Equation of line: y = 3x + 7