Stacy saved 30% on a single item. If she saved $60.00, what was the cost of the item before the discount?
1 answer:
You might be interested in
Answer:
The equation of line a is y = x
The equation of line b is y = x
Step-by-step explanation:
The equation of the proportional is y = m x, where
- m is the slope of the line (constant of proportionality)
The rule of the slope of a line is m = , where
- (x1, y1) and (x2, y2) are two points on the line
∵ Line a passes through points (0, 0) and (3, 3)
∴ x1 = 0 and y1 = 0
∴ x2 = 3 and y2 = 3
→ Substitute them in the rule of the slope above
∵ m =
∴ m = 1
→ Substitute in the form of the equation above
∴ y = (1)x
∴ y = x
∴ The equation of line a is y = x
∵ Line b passes through points (0, 0) and (3, 2)
∴ x1 = 0 and y1 = 0
∴ x2 = 3 and y2 = 2
→ Substitute them in the rule of the slope above
∵ m =
∴ m =
→ Substitute in the form of the equation above
∴ y = () x
∴ y = x
∴ The equation of line b is y = x