Answer:
none of them
Step-by-step explanation:
Two lines are perpendicular when satisfy the next equation: m1*m2 = -1, where m1 and m2 are the slopes o the lines.
line 1:
y – 1 = (x+2)
y = x + 3
slope of line 1 = 1
line 2:
y + 2 = –3(x – 4)
y + 2 =
-3*x + 12
y = -3*x + 10
slope of line 2 = -3
m1*m2 = 1*(-3
) = -3
They are not perpendicular
line 3:
y − 5 = 3(x + 11)
y − 5 = 3*x + 33
y = 3*x + 38
slope of line 3 = 3
m1*m3 = 1*3 = 3
They are not perpendicular
line 4:
y = -3x –
slope of line 4 = -3
m1*m4 = 1*(-3
) = -3
They are not perpendicular
line 5:
y = x – 2
slope of line 5 = 1
m1*m5 = 1*1 = 1
They are not perpendicular
line 6:
3x + y = 7
y = -3x + 7
slope of line 6 = -3
m1*m6 = 1*(-3
) = -3
They are not perpendicular
Our discriminant is 0 so, 
has one real root.
Option C is correct.
Step-by-step explanation:
we need to find the discriminant and the number of real roots for the following equation:
The discriminant is found by using square root part of quadratic formula:
where b =12, a=4 and c=9
Putting values:
To find out the number of real roots using discriminant we have following rules:
- if discriminant b^2-4ac >0 then 2 real roots
- if discriminant b^2-4ac =0 then 1 real root
- if discriminant b^2-4ac <0 then no real roots
Since our discriminant b^2-4ac is 0 so, has one real root.
Option C is correct.
Keywords: discriminant
Learn more about discriminant at:
#learnwithBrainly
Answer:
The answer is 0.6666666667
Step-by-step explanation:
$285×15/100
= $42.75 and this is the discount
$285-42.75 = $242.25
Sally will buy the bicycle at $ 242.25
