Answer:
y = 3x - 1
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
y = 3x + 2 ← is in slope- intercept form
with slope m = 3
Parallel lines have equal slopes , then
y = 3x + c ← is the partial equation
To find c substitute (3, 8 ) into the partial equation
8 = 9 + c ⇒ c = 8 - 9 = - 1
y = 3x - 1 ← equation of parallel line
Rs 120
Let MP = m
Discount = 25% of MP = m/4
SP = MP - Discount
= m - m/4 = 3m/4
If profit is 20%, CP = 3m/4 x 100/120 = 5m/8
=> Profit = 3m/4 - 5m/8 = m/8
Given Profit - Discount = Rs 15
=> |m/8 - m/4| = 15
m/8 = 15
m = Rs 120
